Entire Report - October 2012


National Overview

NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.

Maps and Graphics

Temperature and Precipitation Ranks
U.S. Percentage Areas
More Information

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Note: GHCN-M Data Notice

An omission in processing a correction algorithm led to some small errors on the Global Historical Climatology Network-Monthly dataset (GHCN-M v3.2.0). This led to small errors in the reported land surface temperatures in the October, November, December and Annual U.S. and global climate reports. On February 14, 2013, NCDC fixed this error in its software, included an additional improvement (described below), and implemented both changes as GHCN-M version 3.2.1. With this update to GHCN-M, the Merged Land and Ocean Surface Temperature dataset also is subsequently revised as MLOST version 3.5.3.

The net result of this new version of GHCN-M reveals very small changes in temperature and ranks. The 2012 U.S. temperature is 0.01°F higher than reported in early January, but still remains approximately 1.0°F warmer than the next warmest year, and approximately 3.25°F warmer than the 20th century average. The U.S. annual time series from version 3.2.1 is almost identical to the series from version 3.2.0 and that the 1895-2012 annual temperature trend remains 0.13°F/decade. The trend for certain calendar months changed more than others (discussed below). For the globe, ranks of individual years changed in some instances by a few positions, but global land temperature trends changed no more than 0.01°C/century for any month since 1880.

NCDC uses two correction processes to remove inhomogeneities associated with factors unrelated to climate such as changes in observer practices, instrumentation, and changes in station location and environment that have occurred through time. The first correction for time of observation changes in the United States was inadvertently disabled during late 2012. That algorithm provides for a physically based correction for observing time changes based on station history information. NCDC also routinely runs a .pairwise correction. algorithm that addresses such issues, but in an indirect manner. It successfully corrected for many of the time of observation issues, which minimized the effect of this processing omission.

The version 3.2.1 release also includes the use of updated data to improve quality control and correction processes of other U.S. stations and neighboring stations in Canada and Mexico.

Compared to analyses released in January 2013, the trend for certain calendar months has changed more than others. This effect is related to the seasonal nature of the reintroduced time-of-observation correction. Trends in U.S. winter temperature are higher while trends in summer temperatures are lower. For the globe, ranks of individual years changed in some instances by a few positions, but global temperature trends changed no more than 0.01°C/century for any month since 1880.

More complete information about this issue is available at this supplemental page.

NCDC will not update the static reports from October through December 2012 and the 2012 U.S and Global annual reports, but will use the current dataset (GHCN-M v. 3.2.1 and MLOST v. 3.5.3) for the January 2013 report and other comparisons to previous months and years.

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National Overview:



October Extreme Weather/Climate Events

Supplemental October, January-October, and Sandy Information


  • Climate Highlights — October
  • The average temperature for the contiguous U.S. during October was 53.9°F, just 0.3°F below the long-term average, ending a 16-month streak of above-average temperatures for the lower 48 that began in June 2011.
  • Below-average temperatures stretched from the Canadian border to the Gulf of Mexico during October, with 19 states having monthly temperatures below their 20th century averages. The Southwest and the Northeast were the only two areas of the country with above average temperatures.
  • The October nationally-averaged precipitation total of 2.19 inches was slightly above the long-term average.
  • Wetter-than-average conditions stretched from the Northwest, through the Northern Plains, into the Midwest and the Northeast. Delaware, Maine, Maryland, Michigan, New Jersey, Ohio, and Washington had October precipitation totals among their ten wettest. Below-average precipitation was observed across the Southern Rockies, and Central and Southern Plains. Texas had its ninth driest October on record.
  • The October 30, 2012 U.S. Drought Monitor showed 60.2 percent of the contiguous U.S. was experiencing moderate-to-exceptional drought, less than the 64.6 percent at the beginning of October. Drought conditions improved across parts of the Midwest and Northeast, while drought conditions worsened across parts of the Northern Rockies.
  • Based on NOAA's Residential Energy Demand Temperature Index (REDTI), the contiguous U.S. temperature-related energy demand for October 2012 was near average.
  • Climate Highlights — Post-Tropical Cyclone Sandy
  • Sandy made landfall near Atlantic City, New Jersey on October 29 after it transitioned from a tropical to a post-tropical cyclone. The storm had maximum sustained winds of 80 miles per hour and a central minimum pressure of 946 millibars at landfall. This preliminary pressure reading was potentially a record low for the Northeast coast, and is pending further review. Sandy’s large size, with tropical storm force winds extending nearly 500 miles from the center, led to the large-scale flooding, wind damage, mass power outages, and over 100 fatalities along much of the East Coast.
  • Sandy brought large storm surge and high water levels to much of the coastal Northeast with New Jersey, New York, and Connecticut particularly hard hit. The 13.88-foot observed water level at The Battery in New York City was an all-time record for the location, smashing the previous record set in 1960 during Hurricane Donna by more than three feet. The Delaware River in Philadelphia also reached a new record high water level of 10.6 feet, surpassing the previous record of 10.5 feet which was set in April 2011 from record rainfall. This new record was due to a combination of heavy precipitation and storm surge.
  • Sandy also brought blizzard conditions to the Central and Southern Appalachians, where over a foot of snow fell in six states from North Carolina to Pennsylvania, shattering all time October monthly and single storm snowfall records. Snowfall totals across the highest elevations approached three feet.
  • Climate Highlights — Year-to-Date (January-October)
  • The January-October period was the warmest first ten months of any year on record for the contiguous United States. The national temperature of 58.4°F was 3.4°F above the 20th century average, and 1.1°F above the previous record warm January-October of 2000. During the 10-month period, 21 states were record warm and an additional 25 states had year-to-date temperatures among their ten warmest. Only Washington had a statewide temperature near average for the period.
  • January-October 2012 was the 16th driest such period on record for the contiguous U.S. with a precipitation total 1.9 inches below the average of 24.78 inches.
  • Drier-than-average conditions were present from the Southwest, through the Rockies, across the Plains and into the Midwest. Nebraska and Wyoming were both record dry for the period. Nebraska’s statewide precipitation total of 11.92 inches was 9.40 inches below average, while Wyoming’s precipitation of 6.57 inches was 5.20 inches below average.
  • The Gulf Coast, parts of the Northeast, and the Pacific Northwest were wetter than average during January-October. Washington’s year-to-date precipitation total was 33.23 inches, 7.36 inches above average, and the fourth wettest January-October on record.
  • The U.S. Climate Extremes Index (USCEI), an index that tracks the highest and lowest 10 percent of extremes in temperature, precipitation, drought and tropical cyclones across the contiguous U.S., was nearly twice the average value during the January-October period, and marked the second highest USCEI value for the period. Extremes in warm daytime temperatures, warm nighttime temperatures, and the spatial extent of drought conditions contributed to the record high USCEI value.
  • Based on NOAA's Residential Energy Demand Temperature Index (REDTI), the contiguous U.S. temperature-related energy demand for January-October 2012 was much below average and the lowest year-to-date value in the 118-year period of record.
  • Climate Highlights — 12-month period (November 2011-October 2012)
  • The November 2011-October 2012 period was the warmest such 12-month period on record for the contiguous U.S., with an average temperature of 55.2°F, 3.2°F above the long-term average. This 12-month temperature average was the sixth warmest of any 12-month period on record for the contiguous United States. The seven warmest 12-month periods have all ended during 2012.

Alaska Temperature and Precipitation:

  • Alaska had its 40th coolest October since records began in 1918, with a temperature 0.2°F (0.1°C) above the 1971–2000 average.
  • Alaska had its 37th coolest August-October since records began in 1918, with a temperature 0.2°F (0.1°C) below the 1971–2000 average.
  • Alaska had its 19th coolest January-October since records began in 1918, with a temperature 1.8°F (1.0°C) below the 1971–2000 average.
  • Alaska had its 44th driest October since records began in 1918, with an anomaly that was 1.3 percent below the 1971–2000 average.
  • Alaska had its 27th wettest August-October since records began in 1918, with an anomaly that was 12.2 percent above the 1971–2000 average.
  • Alaska had its 25th wettest January-October since records began in 1918, with an anomaly that was 14.4 percent above the 1971–2000 average.

For additional details about recent temperatures and precipitation across the U.S., see the Regional Highlights section below and visit the Climate Summary page". For information on local temperature and precipitation records during the month, please visit NCDC's Records page. For details and graphics on weather events across the U.S. and the globe please visit NCDC's Global Hazards page.


Regional Highlights:

These regional summaries were provided by the six Regional Climate Centers and reflect conditions in their respective regions. These six regions differ spatially from the nine climatic regions of the National Climatic Data Center.

  • Northeast Region: (Information provided by the Northeast Regional Climate Center)
  • For the fourth month in a row, the Northeast was warmer than normal. October’s average temperature was 51.6 degrees F (10.9 degrees C), which is 2.3 degrees F (1.3 degrees C) above normal. Rhode Island ranked warmest among the states with an average temperature of 55.8 degrees F (13.2 degrees C) making it the 12th warmest October for that state in the past 118 years. West Virginia was the only state cooler than normal with an average temperature of 52.7 degrees F (11.5 degrees C), which is 0.4 degrees F (0.2 degrees C) below average.
  • While October started off dry, Sandy brought record rainfall to parts of the Northeast. With a monthly total of 5.49 inches (139.45 mm), October was 143 percent of normal. Delaware received 8.89 inches (225.81 mm) of rain making it the wettest October since 1895. Maryland had its third wettest October with 7.68 inches (195.07 mm) of rain. Dulles, VA, received 4.25 inches (107.95 mm) on the 29th while Baltimore, MD, received 5.51 inches (139.95 mm) on the same day marking their wettest October calendar days on record. Sandy also brought snow to parts of the Northeast. In fact it was the snowiest October on record (since 1948) for Charleston, WV, with 10.1 inches (256.54 mm). Despite receiving rain from Sandy, Connecticut remained slightly drier than normal at 89 percent. While drought conditions improved across most of the Northeast, upstate New York was still experiencing abnormal dryness (D0) according to the US Drought Monitor for October 30, 2012.
  • An EF0 tornado touched down in Harford County, MD, on the 19th. The same storm system spawned an EF1 tornado in Lancaster County, PA. The tornado injured 15 people and produced an estimated three to five million dollars in tree and structural damage. At the end of the month, Sandy walloped the Northeast with record flooding. The Battery, NY, set a record high water level of 13.88 feet (4.23 m) smashing the old record of 10.02 feet (3.05 m) set by Hurricane Donna in 1960. The water level at Sandy Hook, NJ, reached 13.3 feet (4.05 m) besting the old record of 10.1 feet (3.08 m) also set by Hurricane Donna. Sandy forced The New York Stock Exchange to close for two consecutive days. The last time it closed for two straight days due to weather was the Blizzard of 1888. According to the Department of Energy website, around 7.9 million people across the Northeast were without power during the height of Sandy. In addition, Philadelphia, PA, and Baltimore, MD, set new all-time low station pressure records. Philadelphia’s pressure dropped to 953 mb on the 29th while Baltimore’s dropped to 964.4 mb on the same day. On the 30th a severe thunderstorm embedded in an outer band of Sandy produced a microburst with pockets of wind reaching 90 mph (40 m/s) in southeastern Massachusetts. Early damage estimates put the loss from Sandy between 30 to 50 billion dollars according to CNBC’s website.
  • For more information, please go to the Northeast Regional Climate Center Home Page.
  • Midwest Region: (Information provided by the Midwest Regional Climate Center)
  • The Midwest regional temperature was slightly below normal in September, breaking a string of 11 straight months above normal from October 2011 to August 2012. For the first time since January 2011, none of the nine Midwest states had an above normal statewide temperature. September temperatures ranged from near normal to 3 degrees F (2 C) above normal near Lake Superior. Temperatures were above normal early in the month but the latter part of the month was cooler than normal. Despite the cool September, statewide year-to-date temperatures rank as the warmest or second warmest in the 118-year history for each Midwest state.
  • September precipitation varied drastically from dry in the north to wet in the south. Minnesota recorded its driest September on record (118 years) with many stations recording topped 14 inches (356 mm) at several stations. As a percentage of normal, the totals ranged from less than 10 percent to more than five times normal. Heavy September rains in Ohio (4th wettest) and Kentucky (7th wettest) were in contrast to the drier conditions to the north where Minnesota recorded its driest September and Wisconsin had its 9th driest. June to September was the driest on record in Iowa and May to September was the third driest in Missouri. Year-to-date precipitation totals rank among the top 12 driest years since 1895 in five states: Iowa (4th), Illinois (7th), Missouri (8th), Indiana (12th), and Wisconsin (12th).less than a half inch (13 mm) of rain while precipitation totals in southern Illinois
  • Early freezes hit Minnesota, Wisconsin, and Iowa with the most widespread event on the 23rd and 24th. The freeze was weeks ahead of normal with many locations in Iowa recording their earliest freeze since 1983. Early crop maturity helped to limit the damages.
  • Drought conditions eased in the southern half of the region but further north there was both expansion and intensification of drought. Overall, the Midwest saw an increase from 82 percent to 91 percent of the region in drought during September but severe drought dropped from 50 to 42 percent and extreme drought dropped from 33 to 15 percent. Missouri saw the biggest improvements going from 97 to just 17 percent areal coverage of extreme drought, though the entire state remained in drought. Minnesota saw the biggest expansion and intensification with drought areas increasing from 38 to 96 percent of the state and extreme drought increasing from 0 to 20 percent. Improvements in the southern parts of the Midwest came too late in the year to help the corn crop.
  • Harvest was on pace or ahead of normal for major crops in the Midwest. Corn harvest was ahead of normal across the region. Soybean harvest was near normal in the southeast but well ahead of normal in the northwest.
  • For details on the weather and climate events of the Midwest, see the weekly summaries in the Midwest Climate Watch page.
  • Southeast Region: (Information provided by the Southeast Regional Climate Center)
  • For the third straight month, mean temperatures were near normal across much of the Southeast region. The greatest departures were found across parts of Alabama, northern sections of Georgia and South Carolina, and western sections of North Carolina and Virginia, where monthly temperatures were between 1 and 2 degrees F (0.5 and 1.1 degrees C) below normal. In contrast, monthly temperatures were between 1 and 2 degrees F (0.5 and 1.1 degrees C) above normal across parts of northern Florida extending northward through eastern sections of the Carolinas and Virginia. Monthly temperatures were also above normal across Puerto Rico and the U.S. Virgin Islands. A month after tying its warmest September on record, San Juan, PR recorded its fourth warmest October in a record extending back to 1898. The warmest weather occurred during the first week and towards the end of the month in advance of Sandy, with temperatures exceeding 80 degrees F (26.7 degrees C) as far north as northern Virginia. The coldest weather of the month occurred following the passage of a cold front on the 8th and in the wake of Sandy over the final four days of the month. In both cases, temperatures failed to reach 50 degrees F (10 degrees C) across parts of Virginia and North Carolina, while subfreezing temperatures were observed across the higher elevations of the Southern Appalachians. Over 400 daily low maximum temperatures were tied or broken during these two periods across the Southeast region.
  • Precipitation in October was below average across most of the Southeast. The driest locations were found across central and southern parts of Alabama, Georgia, and South Carolina, where monthly totals were less than 25 percent of normal. Mobile, AL, recorded only 0.19 inches (4.8 mm) for the month, which was 3.5 inches (88.9 mm) below normal, while Macon, GA, recorded only 0.25 inches (6.4 mm) for the month, which was over 2.5 inches (63.5 mm) below normal. In contrast, the wettest locations were found across eastern sections of North Carolina and Virginia, where monthly totals exceeded 200 percent of normal in places. Most of this precipitation came from Sandy, which dropped between 5 and 10 inches (127 and 254 mm) from the 28th to the 31st of the month. Norfolk, VA, recorded its second wettest October with 8.98 inches (228.1 mm) of precipitation (period of record 1874-2012). Sandy’s transitioning to an extratropical circulation produced an early season snowstorm across the Southern Appalachians. Flurries were reported as far south as northern Georgia, while some of the higher elevations of Virginia and North Carolina reported over 10 inches (254 mm) of snowfall. A CoCoRaHS station in western North Carolina (Bakersville 5.4 N) recorded 14.9 inches (378.5 mm) of snowfall from the 29th to the 31st, marking one of the biggest event-total snowfalls on record across the state for the month of October. Precipitation in October was variable across Puerto Rico, with above normal precipitation along the northern half of the island and below normal precipitation along the southern half. Precipitation was generally above normal across the U.S. Virgin Islands, with a large portion tied to the passage of Hurricane Rafael on the 15th of the month.
  • There were only 32 reports of severe weather across the Southeast in October, with at least one report on eight of the 31 days. A total of five tornadoes, all EF-0s, were confirmed across the region. Four of these tornadoes occurred on the 1st of the month, three in Columbus County in southeastern North Carolina and one in Coosa County in central Alabama. The fifth tornado occurred on the 15th of the month in a rural section of Jefferson County, AL. All of these tornadoes were weak and short-lived, resulting in some downed and uprooted trees, minor structural damage, and some isolated power outages.
  • Sandy affected several southeastern states from the 24th to the 31st of the month. Although the center of circulation remained well off the Southeast Atlantic coast, tropical storm force wind gusts were observed as far inland as central Georgia, resulting in scattered power outages. Strong winds, waves, and high tides contributed to storm surge flooding and beach erosion from south Florida to eastern Virginia. Several coastal roads, including parts of Highway 12 along the Outer Banks of North Carolina, were inundated with up to 2 feet (0.6 m) of water. Sandy was also responsible for the sinking of the HMS Bounty, a reconstructed version of the 18th century Royal Navy merchant vessel upon which the infamous Mutiny on the Bounty took place. All 16 crew members except the Captain were rescued after the ship began taking on water roughly 90 miles (144.8 km) off the coast of North Carolina. One of the rescued members later died from his injuries. Heavy rainfall from Sandy also contributed to inland flooding across the region. In Washington D.C., the combination of flooding and power outages forced the closure of federal buildings and tourist sites, as well as the city transit system, from the 29th to the 30th of the month. Sandy also contributed to strong winds across the Southern Appalachians, with gusts exceeding 70 mph (31.3 m/s) across some of the higher elevations. This resulted in scattered power outages and road closures, including sections of the Blue Ridge Parkway.
  • There were relatively few changes to the U.S. Drought Monitor across the Southeast in October. Abnormally dry conditions (D0) expanded across southeastern Georgia, central South Carolina, and south-central North Carolina. There was a slight contraction of moderate (D2) to exceptional (D4) drought across central Georgia, while Sandy helped eliminate drought conditions across eastern and northern sections of Virginia. By the end of the month, approximately 40 percent of the Southeast was classified in drought. The overall dry pattern in October aided in the harvesting of row crops and fall vegetables as well as the planting of winter crops. Pastures were also reported to be in good condition due to the cooler temperatures, though newly planted pastures, particularly fescue and cool season forage, could benefit from some additional rainfall. The continued dry pattern across central Georgia forced some farmers to ship in water for their livestock to offset dropping farm pond levels. Livestock and crop conditions also declined across much of South Carolina due to the lack of rainfall. High winds from Sandy contributed to some cotton damage across eastern North Carolina and delayed the harvesting of several row crops. However, the rain from Sandy provided some much needed moisture for newly planted winter wheat. Several vegetable and tobacco growers in North Carolina reported above average yields for the year, while growers in Virginia reported that peanut and soybean yields have been above average.
  • For more information, please go to the Southeast Regional Climate Center Home Page.
  • High Plains Region: (Information provided by the High Plains Regional Climate Center)
  • October 2012 was actually cooler than normal for the majority of the High Plains Region. Most locations in the Region had average temperatures which were at least 2.0 degrees F (1.1 degrees C) below normal. Above normal average temperatures were limited to southwestern Colorado and portions of southern Wyoming. The cooler weather was not record-breaking although there were a few locations that were able to creep into the top 10 coolest Octobers on record. Garden City, Kansas tied for its 6th coolest October on record with an average temperature of 52.3 degrees F (11.3 degrees C). The record of 48.6 degrees F (9.2 degrees C) occurred just a few years ago in 2009 (period of record 1947-2012). Despite the widespread below normal temperatures this month, 2012 still continued to be one of the warmest on record in many places. For example, the average temperature in Grand Forks, North Dakota was 1.3 degrees F (0.7 degrees C) below normal this month, but this year’s January 1-October 31 time period still ranked as the warmest. The average temperature in Grand Forks for this time period was 48.7 degrees F (9.3 degrees C), which surpassed the 1931 record of 48.1 degrees F (8.9 degrees C) (period of record 1893-2012).
  • Ample precipitation was confined to North Dakota and small pockets elsewhere in the High Plains Region this month. Much needed precipitation fell in areas of northern North Dakota, where precipitation totals were over 150 percent of normal. While this precipitation was not record-breaking, it did help alleviate drought conditions there. In addition, many locations across the High Plains Region had their first snowfall of the season this month. Even with the snowfall, a large portion of the High Plains Region continued to have dry conditions this month. Central Nebraska, central South Dakota, southern Kansas, southern and northwestern Colorado, and south-central Wyoming all had precipitation totals which were less than 25 percent of normal. The dry weather helped with the harvesting of row crops in many areas across the Region. The corn harvest was ahead of average in Kansas, Nebraska, North Dakota, and South Dakota. The soybean harvest was also well ahead of average in Nebraska, North Dakota, and South Dakota. On the downside, dryness continued to affect pasturelands as most of the Region continued to have pasture conditions in the very poor to poor classifications. Dry and windy conditions also took their toll on winter wheat progress. For instance, the lack of precipitation limited winter wheat emergence in parts of South Dakota and some winter wheat had to be reseeded in Nebraska due to wind damage. Although mid-October showers did help with winter wheat emergence, according to the National Agricultural Statistics Service (NASS), more precipitation is needed for improved emergence.
  • Slight changes in drought conditions in the High Plains Region occurred over the past month, according to the U.S. Drought Monitor. Some areas experienced improvements and others had degradation which balanced out to little change over the past month. Nebraska was still the hardest hit state, with nearly 78 percent of the state in exceptional drought conditions (D4) which was up a few percent from the end of last month. South Dakota had the most degradation with a significant increase in D4 that went from 7 to 33 percent coverage over the past month. The most significant improvements occurred in the Red River Valley of North Dakota where precipitation in the middle of the month helped downgrade all extreme drought conditions (D3) to severe drought conditions (D2) in the state. Other areas which had improvements included north central Colorado, eastern Kansas, far southeastern Nebraska, and central North Dakota. According to the U.S. Seasonal Drought Outlook released November 1st, drought conditions were expected to improve across the entire state of North Dakota and northern areas of South Dakota. All other areas of drought in the Region were expected to persist through the end of January 2013.
  • Even with the growing season coming to a close, the ongoing drought has continued to have impacts across the Region. The combination of an intense low pressure system to the east and high pressure over the Rockies created very strong northwest winds over the High Plains Region October 17-18. The strongest wind speeds occurred on the 18th when winds were sustained at 35-45 mph (56-72 km/h) for much of the day. Gusts to 50-60 mph (80-97 km/h) were quite common and some peak wind gusts topping 70 mph (113 km/h) were reported as well. The combination of these winds and dry conditions from the ongoing drought caused a large dust storm to form. The dust storm reduced visibilities and many roads were forced to close, including portions of I-80 in western Nebraska and eastern Wyoming, I-70 in eastern Colorado, and I-35 in Kansas and Oklahoma. Unfortunately, wildfires also started during this time period and spread rapidly. According to NASS, in Nebraska, buildings, machinery, and even crops were lost in these fires. Impacts ranging from overturned semi-trucks to downed power lines to roof and tree damage were reported all across the wind swept region.
  • For more information, please go to the High Plains Regional Climate Center Home Page.
  • Southern Region: (Information provided by the Southern Regional Climate Center)
  • October was a slightly cooler than normal month for much of the Southern Region. Slightly warmer than normal temperatures were observed in southern and western Texas. Elsewhere, temperatures averaged between 0 to 4 degrees F (0 to 2.22 degrees C) below expected values. The lowest temperature averages occurred in the central parts of the region where temperatures ranged between 2 to 4 degrees F (1.11 to 2.22 degrees C) below normal. The state average temperature values are as follows: Arkansas reported 58.90 degrees F(14.94 degrees C), Louisiana reported 65.50 degrees F (18.61 degrees C), Mississippi reported 61.50 degrees F (16.39 degrees C), Oklahoma reported 59.50 degrees F (15.28 degrees C), Tennessee reported 56.50 degrees F (13.61 degrees C) and Texas reported 65.70 degrees F(18.72 degrees C). For Mississippi, it was the fifteenth coldest October on record (1895-2012), while for Arkansas, it was their sixteenth coldest October on record (1895-2012). In Tennessee it was their twentieth coldest October on record (1895-2012), and it was the twenty-third and twenty-fourth coldest October on record (1895-2012) for Louisiana and Oklahoma, respectively. Lastly, the state of Texas recorded its forty-third coldest October on record (1895-2012).
  • With the exception of Tennessee and northern Mississippi, October was much drier than normal month in the Southern Region. A large portion of the region, including Oklahoma, Texas, Louisiana and southern Mississippi, received approximately half the normal amount of precipitation or less. Conditions were extremely dry throughout much of northwestern Texas and central Oklahoma, with many stations receiving only 5 to 25 percent of normal precipitation. Texas averaged only 0.83 inches (21.08 mm) of precipitation, making it their ninth driest October on record (1895-2012). The state of Oklahoma averaged 1.28 inches (32.51 mm), which is their twentieth driest October on record (1895-2012). Louisiana experienced its thirty-sixth driest October on record (1895-2012) with a state average precipitation of 1. 83 inches (46.48 mm). Conversely, conditions were wetter than normal in Tennessee. The state averaged 4.03 inches (102.40 mm), making it their twenty-fourth wettest October (1895-2012). Other state average precipitation values include Mississippi, which averaged 3.56 inches (90.42 mm) and Arkansas, which averaged 3.33 inches (84.58 mm).
  • Despite widespread dryness in October over much of the Southern Region, drought conditions have not changed significantly over the past month. Slight improvements occurred in western Tennessee and in northern Mississippi. There was also a one category improvement in northern Arkansas, which improved from exceptional drought to severe and extreme drought. Elsewhere, conditions remained relatively unchanged.
  • On October 1, 2012, a series of Tornadoes touched down in central Tennessee. No injuries or fatalities were reported. Damage appears to have been primarily to trees and power lines.
  • Some hail-induced windshield damage was reported in Hale County, Texas on October 12. Hail size varied from golfball sized and smaller. Two tornadoes were reported but no damage, injuries or fatalities were listed.
  • Dozens of wind and hail reports occurred on October 13, 2012. These ranged from northwestern Arkansas, to central Texas. Some tornadoes were reported, but no details were available on the amount damage that occurred.
  • October 17, 2012 was the busiest day in the Southern Region for severe weather. Several tornadoes were reported in Mississippi and Arkansas. A few homes were damaged in Bolivar County Mississippi, while power lines and trees were reported down in Monroe County Arkansas. A tornado in Sharkey County, Mississippi damaged several mobile homes and a total of four injuries were reported. A second tornado in Sharkey County resulted in five injuries. The report lists that several homes along highway 14 were damaged. Similar damage, without injury, occurred in Humphreys County Mississippi as well. Several trees were snapped, outbuildings and travel trailed incurred some damage from the storm.
  • For more information, please go to the Southern Regional Climate Center Home Page.
  • Western Region: (Information provided by the Western Regional Climate Center)
  • Storms began marching across the Pacific Northwest mid-month, providing the first relief from a summer dominated by below normal precipitation and developing drought. Dry conditions persisted throughout the Southwest with the exception of southern Nevada, where a slow moving low-pressure system generated heavy precipitation and thunderstorms.
  • A storm system with a tap into subtropical moisture brought substantial precipitation to Washington, northern Oregon, the Idaho Panhandle, and western Montana on the 29th-31st, pushing many of these regions into one of their top 10 wettest Octobers on record. The windward side of the Olympic range in Washington received 7.5 to 9 in (190-230 mm) of rain during the 3-day event. After receiving no measurable precipitation for 84 days (July 21-Oct 12), Wenatchee, Washington recorded 1.56 in (39.6 mm) this month, 354% of normal and Wenatchee’s 3rd wettest October on record. Seattle-Tacoma Airport, Washington recorded its 4th wettest October in a record beginning in 1948 with 6.71 in (170.4 mm), 193% of normal for the month. Further east, Missoula, Montana logged 1.82 in (46.2 mm) total precipitation and 4 in (10.2 cm) snow, making for the 6th wettest and 7th snowiest October in a record that began in 1893. Despite high precipitation totals this month, 60% of Montana remains in moderate to extreme drought.
  • Las Vegas, Nevada saw its 9th wettest October in a record beginning in 1888 with a total of 0.73 in (18.5 mm). In just 3 months, August 1-October 31, 2012, Las Vegas received 4.19 in (106.4 mm) of precipitation, equal to the location’s 30-year normal for annual precipitation. In contrast, the first 6 months of 2012 saw only 0.25 in (6.35 mm) in Las Vegas, the 6th driest January-June period on record. The same storm system that brought precipitation to the Las Vegas area also provided rainfall to Colorado’s Front Range, helping to alleviate the persistent drought in this region. A cold front passed through the Front Range late in the month, bringing over 5 in (12.7 cm) of snowfall to Denver, bringing the city’s total to 1.22 in (31.0 mm) of precipitation for October, 119% of normal. Wyoming also received some drought relief this month from the aforementioned storm systems. Normal to slightly above normal precipitation fell in the western and southeastern portions of the state, though at month’s end, 97.8% of Wyoming remained at some level of drought. In the Southwest, Albuquerque, New Mexico recorded only trace precipitation this month, tying the 2nd driest October since official records began in 1933.
  • In addition to dry conditions, above normal temperatures dominated the Southwest. Phoenix, Arizona recorded its 8th warmest October at 78.8 F (26.0 C), and Albuquerque, New Mexico noted its 10th warmest at 60.8 F (16 C). Records at Phoenix date back to 1895 and at Albuquerque to 1892. On October 6th, Ely, in northeastern Nevada, saw its second latest autumn freeze in an 89-year record, behind October 13, 1963. On the heels of its warmest August and September on record, Reno, Nevada posted an average October temperature of 58 F (14.4 C), the 5th warmest in a record beginning in 1888.
  • Much further north, most of interior and southeast Alaska saw near or below normal temperatures this month. In contrast, the North Slope recorded average monthly temperatures 8-10 F (4-5 C) above normal. Barrow posted an October average of 27.5 F (-2.5 C), 10.3 F (5.7 C) above normal and the warmest since records began in 1949. This warmth is likely associated with the smallest measured summer minimum of polar ice extent, well below the former 2007 record. Out in the Pacific, Lihue, Hawaii set an all-time October high temperature record of 91 F (32.8 C) on October 9th. Lihue also recorded its driest October in a record that began in 1950, receiving only 0.39 in (9.9 mm) of rainfall, 9% of normal. Hilo, Hawaii also had a dry October at a total of 2.91 in (73.9 mm), its 3rd driest on record. All reporting stations in Hawaii received 75% or less of their normal October rainfall, further exacerbating the persistent drought conditions on the lee sides of the Islands.
  • Sierra Snowfall: In a 4-day event beginning October 22nd, the Sierra Nevada received its first significant snowfall of the season. The Central Sierra Snow Lab two miles west of Donner Summit reported a maximum snow depth of 29 in (74 cm) on October 25th. This is the highest October snowfall total in the last 8 years at this location. October is typically hit-or-miss as the start to the winter snow season in the Sierra, with many station records for the region showing a mix of zero-snowfall Octobers and totals over 1 ft (30.5 cm).
  • For more information, please go to the Western Regional Climate Center Home Page.

See NCDC's Monthly Records web-page for weather and climate records for the most recent month. For additional national, regional, and statewide data and graphics from 1895-present, for any period, please visit the Climate at a Glance page.


PLEASE NOTE: All of the temperature and precipitation ranks and values are based on preliminary data. The ranks will change when the final data are processed, but will not be replaced on these pages. Graphics based on final data are provided on the Temperature and Precipitation Maps page and the Climate at a Glance page as they become available.

Global Analysis

Contents of this Section:


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Note: GHCN-M Data Notice

An omission in processing a correction algorithm led to some small errors on the Global Historical Climatology Network-Monthly dataset (GHCN-M v3.2.0). This led to small errors in the reported land surface temperatures in the October, November, December and Annual U.S. and global climate reports. On February 14, 2013, NCDC fixed this error in its software, included an additional improvement (described below), and implemented both changes as GHCN-M version 3.2.1. With this update to GHCN-M, the Merged Land and Ocean Surface Temperature dataset also is subsequently revised as MLOST version 3.5.3.

The net result of this new version of GHCN-M reveals very small changes in temperature and ranks. The 2012 U.S. temperature is 0.01°F higher than reported in early January, but still remains approximately 1.0°F warmer than the next warmest year, and approximately 3.25°F warmer than the 20th century average. The U.S. annual time series from version 3.2.1 is almost identical to the series from version 3.2.0 and that the 1895-2012 annual temperature trend remains 0.13°F/decade. The trend for certain calendar months changed more than others (discussed below). For the globe, ranks of individual years changed in some instances by a few positions, but global land temperature trends changed no more than 0.01°C/century for any month since 1880.

NCDC uses two correction processes to remove inhomogeneities associated with factors unrelated to climate such as changes in observer practices, instrumentation, and changes in station location and environment that have occurred through time. The first correction for time of observation changes in the United States was inadvertently disabled during late 2012. That algorithm provides for a physically based correction for observing time changes based on station history information. NCDC also routinely runs a .pairwise correction. algorithm that addresses such issues, but in an indirect manner. It successfully corrected for many of the time of observation issues, which minimized the effect of this processing omission.

The version 3.2.1 release also includes the use of updated data to improve quality control and correction processes of other U.S. stations and neighboring stations in Canada and Mexico.

Compared to analyses released in January 2013, the trend for certain calendar months has changed more than others. This effect is related to the seasonal nature of the reintroduced time-of-observation correction. Trends in U.S. winter temperature are higher while trends in summer temperatures are lower. For the globe, ranks of individual years changed in some instances by a few positions, but global temperature trends changed no more than 0.01°C/century for any month since 1880.

More complete information about this issue is available at this supplemental page.

NCDC will not update the static reports from October through December 2012 and the 2012 U.S and Global annual reports, but will use the current dataset (GHCN-M v. 3.2.1 and MLOST v. 3.5.3) for the January 2013 report and other comparisons to previous months and years.

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Global Highlights

  • The average combined global land and ocean surface temperature for October 2012 tied with 2008 as the fifth warmest October on record, at 0.63°C (1.13°F) above the 20th century average of 14.0°C (57.1°F). Records began in 1880.

  • The globally-averaged land surface temperature for October 2012 was the eighth warmest October on record, at 0.92°C (1.66°F) above average. The globally-averaged ocean surface temperature tied with 2004 as the fourth warmest October on record, at 0.52°C (0.94°F) above average.

  • The average combined global land and ocean surface temperature for January–October 2012 was the eighth warmest such period on record, at 0.58°C (1.04°F) above the 20th century average.


==global-temps-errata==

Introduction

Temperature anomalies and percentiles are shown on the gridded maps below. The anomaly map on the left is a product of a merged land surface temperature (Global Historical Climatology Network, GHCN) and sea surface temperature (ERSST.v3b) anomaly analysis developed by Smith et al. (2008). Temperature anomalies for land and ocean are analyzed separately and then merged to form the global analysis. For more information, please visit NCDC's Global Surface Temperature Anomalies page. The October 2012 Global State of the Climate report introduces percentile maps that complement the information provided by the anomaly maps. These new maps on the right provide additional information by placing the temperature anomaly observed for a specific place and time period into historical perspective, showing how the most current month, season or year compares with the past.

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Temperatures

In the atmosphere, 500-millibar height pressure anomalies correlate well with temperatures at the Earth's surface. The average position of the upper-level ridges of high pressure and troughs of low pressure—depicted by positive and negative 500-millibar height anomalies on the October 2012 height and anomaly mapOctober 2012 map—is generally reflected by areas of positive and negative temperature anomalies at the surface, respectively.

October

The average temperature across land and ocean surfaces during October was 14.63°C (58.23°F). This is 0.63°C (1.13°F) above the 20th century average and ties with 2008 as the fifth warmest October on record. The record warmest October occurred in 2003 and the record coldest October occurred in 1912. This is the 332nd consecutive month with an above-average temperature. The last below-average month was February 1985. The last October with a below-average temperature was 1976. The Northern Hemisphere ranked as the seventh warmest October on record, while the Southern Hemisphere ranked as second warmest, behind 1997.

The average global temperature over land was 0.92°C (1.66°F) above average, making this the eighth warmest October on record. Several regions around the globe were much warmer than average, including northeastern and southwestern North America, most of South America, northern Africa, southeastern Europe, southwestern Asia, and far eastern Russia. A heat wave brought record warmth to large areas of Brazil and Bolivia. Record heat was also present in southern India. It was cooler than average in parts of northern Siberia, Mongolia, and northern China along with much of central North America. Western Canada was much cooler than average.

Select national information is highlighted below:
  • The average monthly temperature across the United Kingdom was 1.3°C (2.3°F) below the 1981–2010 average, making this the coldest October since 2003. Regionally, Scotland had its seventh coolest October since records began in 1910 and coolest since 1993.

  • Central and southeastern Europe were warmer than average during October. Temperatures were about 1.1 to 1.6°C (2.0 to 2.9°F) above the 1961–1990 average across large parts of Croatia, particularly in the south and west, while the Republic of Moldova reported monthly temperatures across the country that ranged from 2.5 to 3.5°C (4.5 to 6.3°F) above average.

  • Every state and territory in Australia observed above-average monthly maximum temperatures during October. The nationally-averaged temperature was 1.53°C (2.75°F) above the 1961–1990 average, making this the 10th warmest October maximum temperature since records began in 1950.

The October global sea surface temperature was 0.52°C (0.94°F) above the 20th century average of 15.9°C (60.6°F). This ties with 2004 as the fourth highest on record for October. The northwestern Atlantic Ocean and part of the north central Pacific Ocean temperatures were markedly higher than average. Conversely, much of the eastern and part of the western Pacific Ocean and much of the southern Atlantic Ocean were below average.

Borderline neutral / weak El Niño conditions were present during October across the central and eastern equatorial Pacific Ocean, with sea surface temperatures close to 0.5°C (0.9°F) above average for a three-month period (August-September-October), the official threshold for the onset of El Niño conditions. According to NOAA's Climate Prediction Center, neutral conditions are expected to continue through the Northern Hemisphere winter 2012/13.

October Anomaly Rank
(out of 133 years)
Records
°C °F Year(s) °C °F
Global
Land +0.92 ± 0.12 +1.66 ± 0.22 Warmest 8th 2005 +1.16 +2.09
Coolest 126th 1912 -0.97 -1.75
Ocean +0.52 ± 0.04 +0.94 ± 0.07 Warmest 4th 2003 +0.59 +1.06
Coolest 130th 1909 -0.47 -0.85
Ties: 2004
Land and Ocean +0.63 ± 0.07 +1.13 ± 0.13 Warmest 5th 2003 +0.73 +1.31
Coolest 129th 1912 -0.57 -1.03
Ties: 2008
Northern Hemisphere
Land +0.88 ± 0.11 +1.58 ± 0.20 Warmest 8th 2011 +1.33 +2.39
Coolest 126th 1912 -1.28 -2.30
Ocean +0.55 ± 0.04 +0.99 ± 0.07 Warmest 5th 2003, 2006 +0.66 +1.19
Coolest 129th 1912 -0.50 -0.90
Ties: 1997
Land and Ocean +0.68 ± 0.09 +1.22 ± 0.16 Warmest 7th 2003 +0.89 +1.60
Coolest 127th 1912 -0.79 -1.42
Southern Hemisphere
Land +1.04 ± 0.15 +1.87 ± 0.27 Warmest 4th 2006 +1.14 +2.05
Coolest 130th 1910 -0.74 -1.33
Ocean +0.51 ± 0.04 +0.92 ± 0.07 Warmest 3rd 1997 +0.59 +1.06
Coolest 131st 1910 -0.47 -0.85
Land and Ocean +0.60 ± 0.06 +1.08 ± 0.11 Warmest 2nd 1997 +0.62 +1.12
Coolest 132nd 1910 -0.51 -0.92
Ties: 2002
Year-to-date (January–October)

Record to near-record warmth over land from April to September and above-average sea surface temperatures across much of the world's oceans resulted in the first ten months of 2012 ranking as the eighth warmest such period on record, with a combined global land and ocean average surface temperature of 0.58°C (1.04°F) above average. With borderline ENSO-neutral / El Niño conditions continuing to hold during October, this is just slightly higher than the January–September year-to-date temperature of 0.57°C (1.03°F) above average. If this anomalous warmth continues through the end of the year, 2012 will surpass 2011 as the warmest La Niña year since the Climate Predition Center began monitoring ENSO conditions in 1950.

Similar to the January–September period, the global land surface temperature for January–October ranked as eighth warmest and the global sea surface temperature ranked as 10th warmest. Much of the United States, south central Canada, northern Argentina, part of southern Europe, parts of the northwestern and southern Atlantic Ocean, and parts of the southern Indian Ocean have all experienced record warmth for the year-to-date.

January–October Anomaly Rank
(out of 133 years)
Records
°C °F Year(s) °C °F
Global
Land +0.94 ± 0.21 +1.69 ± 0.38 Warmest 6th 2007 +1.09 +1.96
Coolest 128th 1893 -0.62 -1.12
Ocean +0.44 ± 0.04 +0.79 ± 0.07 Warmest 10th 1998 +0.54 +0.97
Coolest 124th 1911 -0.48 -0.86
Ties: 1997
Land and Ocean +0.58 ± 0.09 +1.04 ± 0.16 Warmest 8th 2010 +0.67 +1.21
Coolest 126th 1911 -0.48 -0.86
Northern Hemisphere
Land +1.04 ± 0.26 +1.87 ± 0.47 Warmest 4th 2007 +1.22 +2.20
Coolest 130th 1883, 1884 -0.72 -1.30
Ocean +0.45 ± 0.05 +0.81 ± 0.09 Warmest 8th 2005 +0.56 +1.01
Coolest 126th 1913 -0.48 -0.86
Ties: 2002, 2007
Land and Ocean +0.67 ± 0.15 +1.21 ± 0.27 Warmest 6th 2010 +0.77 +1.39
Coolest 128th 1913 -0.50 -0.90
Southern Hemisphere
Land +0.68 ± 0.13 +1.22 ± 0.23 Warmest 8th 2005 +0.92 +1.66
Coolest 126th 1917 -0.67 -1.21
Ocean +0.45 ± 0.04 +0.81 ± 0.07 Warmest 10th 1998 +0.57 +1.03
Coolest 124th 1911 -0.51 -0.92
Ties: 1997
Land and Ocean +0.48 ± 0.07 +0.86 ± 0.13 Warmest 9th 1998 +0.62 +1.12
Coolest 125th 1911 -0.52 -0.94
Ties: 2001

The most current data may be accessed via the Global Surface Temperature Anomalies page.

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Images of sea surface temperature conditions are available for all weeks during 2012 from the weekly SST page.


Precipitation

The maps below represent precipitation percent of normal (left) and precipitation percentiles (right) based on the GHCN dataset of land surface stations using a base period of 1961–1990. As is typical, precipitation anomalies during October 2012 varied significantly around the world.

  • Western parts of Finland observed precipitation totals that were double the October monthly average. Some stations broke their all-time highest monthly precipitation records for October.

  • Sandy dumped copious rain over Jamaica, Haiti, the Dominican Republic, Cuba, and much of the eastern United States. Sandy also brought blizzard conditions to the Central and Southern Appalachians, shattering all-time U.S. October monthly and single storm snowfall records.

  • October was dry across Australia, with the continent experiencing rainfall that was 48 percent of average for the month. This was the 10th driest October since precipitation records began in 1900. South Australia was fifth driest on record, reporting just 18 percent of average rainfall.

Additional details on flooding and drought events around the world can also be found on the October 2012 Global Hazards page.

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References

Peterson, T.C. and R.S. Vose, 1997: An Overview of the Global Historical Climatology Network Database. Bull. Amer. Meteorol. Soc., 78, 2837-2849.

Quayle, R.G., T.C. Peterson, A.N. Basist, and C. S. Godfrey, 1999: An operational near-real-time global temperature index. Geophys. Res. Lett., 26, 333-335.

Smith, T.M. and R.W. Reynolds, 2005: A global merged land air and sea surface temperature reconstruction based on historical observations (1880-1997), J. Clim., 18, 2021-2036.

Smith et al., 2008, Improvements to NOAA's Historical Merged Land-Ocean Surface Temperature Analysis (1880-2006), J. Climate., 21, 2283-2293.

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Global Hazards

Please note: Material provided in this report is chosen subjectively and included at the discretion of the National Climatic Data Center (NCDC). The ability to report on a given event is limited by the amount of information available to NCDC at the time of publication. Inclusion of a particular event does not constitute a greater importance in comparison with an event that has not been incorporated into the discussion. Data included in this report are preliminary unless otherwise stated. Links to supporting information are valid at the time of publication, but they are not maintained or changed after publication.


Updated 21 November 2012


October 2012Dry and warm conditions persisted in Australia. read more October 2012Massive dust storm obscured parts of central U.S. read more October 2012Bulgaria basked under heatwave. read more October 2012Torrential rains inundated cities in France, Africa, and Argentina read more October 22ndTwisters made rare appearance in western U.S. read more October 2012Hurricanes roared in four of five ocean basins. read more October 28thHeavy snowfall blanketed parts of Europe. read more October 11thRare snowfall swirled through southern Australian mountains. read more October 2012Sea ice thickness changes motivated research read more



Drought conditions

Bushfires in northern Australia on 13 October 2012
Bushfires in northern Australia
on 13 October 2012
Source: NASA Earth Observatory

Below-average rainfall during October in north and central Australia bolstered the bushfire threat. Dry lightning ignited numerous bushfires along border areas of the Northwest Territory and Western Australia at mid-month. October's average rainfall in southern Australia was the lowest on record since 1900. In early October, two fires in New South Wales threatened more than 20 coastal homes as gusty winds spread the flames. One of the fires erratically burned near a coal mining operation and forced a closure of the train services between Sydney and Newcastle while charring almost 1,500 acres, according to media reports. During October, efforts to construct Australia's first bushfire resistant home were underway in rural Victoria. The structure — made with steel frame, magnesium oxide, and straw bale insulation — withstood over 1000°C (1832°F) for nearly two minutes in bushfire simulations.


U.S. Great Plains Dust Storm on 18 October 2012
U.S. Great Plains Dust Storm
on 18 October 2012
Source: NASA Earth Observatory

In the U.S., persistent exceptional drought across the Great Plains combined with ferocious northwest winds with gusts topping 113 kph (70 mph) to render a widespread dust storm on October 18th spanning several states. Reduced visibilities closed sections of interstate highways in the states of Nebraska, Wyoming, Colorado, Oklahoma, and Kansas. In Oklahoma, a major traffic accident involving over 30 cars and tractor-trailers occurred during the dust storm, resulting in nine persons being injured, according to media reports. Strong winds and drought in the southwestern corner of North Dakota fueled a grassland fire which destroyed 4 homes and 20 other structures, while engulfing over 6,000 acres near the town of Bucyrus at mid-month. Please see NOAA's Wildfires page for additional information.

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Extreme Temperatures

Bulgaria experienced record high temperatures during October. Five new records for daily maximum temperatures were set on October 1st in the cities of Lovech, Blagoevgrad, Dragoman, Sofia, and Shabala, ranging from 34.9°C (94.8°F) to 25.4°C (77.7°F). Moreover, the records were part of a multi-day streak (begun during September) of unusually warm autumn temperatures, as strong southerly winds blew across the country. On October 16th seven new daily maximum temperature records were set, while on October 28th new extremes occurred at five locations, according to media reports.

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Heavy rainfall and flooding

Above-normal rainfall occurred across much of France during October. The country averaged 107 mm (4.2 inches) for the month, which was 31 percent more than its normal based on the 1981-2010 period of record. Torrential rains in southwestern France inundated the mountain town of Lourdes beginning on October 18th, according to media reports. Flooding of the Gave de Pau River on October 20th resulted in evacuation of more than 420 hotel guests making pilgrimages to the religious shrine as waist-high water filled local streets and buildings. The Red Cross provided assistance with food and shelter. Flash flooding deposited up to 20 cm (8 inches) of mud and debris in the famed grotto and clogged water pumps for the bath halls. Floating tree trunks rendered damages to a hydroelectric power plant and bridges in excess of an estimated $2.5 million U.S. dollars. About six million people visit the Grotto of Lourdes attraction annually.

Heavy rains in central Africa caused flooding within northern areas of the Democratic Republic of Congo between late September and the end of October. Three fatalities resulted and 300 homes collapsed during flooding in the town of Gbadolite (Equateur Province) from September 27th–29th, according to humanitarian agency reports. The Red Cross responded to restore drinking water and food supplies. River flooding in the Orientale Province affected at least 3,400 households where the residents of villages in Dungu and Niangara lost homes and plantations and faced increased risks of cholera and malaria.

Intense storms battered southern Argentina with heavy rain and hail in late October. As much as 200 mm (8 inches) of precipitation fell within two hours in Buenos Aires on the morning of October 29th, according to media reports. Two fatalities (one from drowning, another from electrocution) resulted from the flooding of the Rio de La Plata areas, where nearly 3,000 people were evacuated to shelters. Transportation services were disrupted while widespread power outages led to numerous traffic accidents.

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Severe Storms

U.S. Storm Report for 22 October 2012
U.S. Storm Report
for 22 October 2012
Source: NOAA Storm Prediction Center

In the U.S., a rare sighting of tornadoes in northern California occurred on October 22nd. Fallen trees and downed power lines resulted as a powerful storm passed through several counties, as well as damages to rooftops and some structures. Please visit NOAA's Tornadoes page for detailed information.

The storm also brought the state its first snowfall of the season. About 25 mm (1 inch) of rain fell in the capital city of Sacramento, with up to 152 mm (6 inches) of snow falling to the east where five tractor-trailer trucks wrecked along California Highway 20 near Nevada City, according to media reports. Heavy snow of up to 0.6 meters (2 feet) fell over the Sierra Nevada range, which helped to replenish the state's water reservoirs.

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Tropical Cyclones

GOES View of Hurricane Sandy on 28 October 2012
GOES View of Hurricane Sandy
on 28 October 2012
Source: NASA Earth Observatory

The hurricane season's above-average activity in the Atlantic Basin continued during October as three tropical storms and two hurricanes developed. Tropical storms included Oscar (Oct 3rd–5th), which formed west of the Cape Verde Islands, Patty (Oct 11th–13th), which skirted the eastern edge of the Bahamas, and Tony (Oct 20th–25th), which remained at sea to the southwest of the Azores. Hurricane Rafael (Oct 12th–17th) brushed by Bermuda, bringing strong winds and rain while about 400 homes lost power and one person perished. Sandy (Oct 22nd–30th) originated in the Caribbean Sea, making landfalls in Jamaica, Cuba, and the United States. At least 170 fatalities resulted from the massive storm. In addition to the devastating impacts of large-scale flooding, wind damage, and power outages at over 8 million households, Sandy brought blizzard conditions to several U.S. states along the Appalachian Mountains. Please visit NOAA's National Overview and the Hurricanes and Tropical Storms pages for detailed information.


Hurricane Paul neared Mexico on 15 October 2012
Hurricane Paul neared Mexico
on 15 October 2012
Source: NASA Earth Observatory

Moderate activity continued in the Eastern Pacific as two tropical storms and one hurricane formed during October. Tropical Storms Olivia (Oct 6th–9th) and Rosa (Oct 30th–Nov 4th) remained entirely at sea to the southwest of Mexico. Hurricane Paul (Oct 13th–17th) made landfall in Mexico's Baja peninsula on October 17th, which resulted in flooding and power losses affecting nearly 16,000 people and damaged close to 1,000 homes, according to media reports. A major port at San Carlos was closed in advance of the storm, as well as four smaller ports used by locals to fish shrimp, tuna, and sardines.


Typhoon Prapiroon weakened along Japan on 18 October 2012
Typhoon Prapiroon weakened along
Japan on 18 October 2012
Source: NASA Earth Observatory

The Western Pacific's very active season continued during October with two typhoons and one tropical storm occurring. Typhoon Prapiroon (a.k.a. Nina; Oct 5th–19th) formed northeast of Guam, then meandered in the Philippines Sea before tracking to the northeast of Japan, while its heavy rains drenched the archipelago islands. Tropical Storm Maria (Oct 13th–20th), which emerged near the Northern Mariana Islands, also tracked northeast of Japan.


Typhoon Son-Tinh lashed Vietnam on 28 October 2012
Typhoon Son-Tinh lashed
Vietnam on 28 October 2012
Source: NASA Earth Observatory

Typhoon Son-Tinh (a.k.a Ofel; Oct 19th–30th) developed in the western Pacific Ocean, and crossed the Philippines before making landfall in Vietnam. As many as 35 people died as a result of the storm, according to media reports. In the Philippines, where the storm caused landslides and flash floods, at least 27 persons were killed with 19 injured, and at least 9 others were missing. In Vietnam, the Category 3 typhoon caused 7 deaths, injured over 40 people, and left 5 others missing as well as downed power lines, destroyed 47,000 acres of rice crops, and damaged more than 13,000 Vietnamese homes. Another death in southern China was attributed to the typhoon, while at least five others were missing, and close to 126,000 residents were evacuated.

Three tropical cyclones developed in the North Indian Basin during October marking the start of its hurricane season. Tropical Depression Bay of Bengal (BOB) 01 (Oct 10th–11th), which formed from a remnant of Tropical Storm Gaemi , battered the southeast coast of Bangladesh, resulted in at least 30 fatalities and over 180 persons injured, with close to 60 fisherman missing, according to media reports. The storm uprooted trees, disrupted electricity, and affected over 100,000 people. At least 30,000 homes (constructed of mud, straw, and tin) were destroyed. Winds and tidal surge caused losses of crops and livestock. The island of Hatiya was considered to be the worst-hit. Humanitarian efforts mobilized to provide tarpaulins, water, and food including pressed rice and molasses. Tropical Storm Murjan (Oct 23rd–26th) developed in the Arabian Sea and made landfall in the Horn of Africa, where it brought heavy rains to northern Somalia, Djibouti, and eastern Ethiopia.


Tropical Storm Nilam crossed North Indian Ocean on 01 November 2012
Tropical Storm Nilam crossed North
Indian Ocean on 01 November 2012
Source: NASA Earth Observatory

Tropical Storm Nilam (Oct 28th–Nov 2nd), formed in the Bay of Bengal and made landfall on the southern Indian coast near Chennai. According to media accounts, the storm, which caused at least 8 fatalities in India and Sri Lanka, displaced over 8,500 people in the Indian state of Tamil Nadu as storm surge of up to 1.5 m (5 ft) flooded its low-lying areas. One of the deaths occurred when a life boat capsized during the rescue efforts of a 37-member crew of a stranded oil tanker. The storm damaged roads, uprooted trees, disrupted power and rail services, and submerged standing crops of rice and bananas. Nuclear reactors at the Madras Atomic Power Station were safeguarded and no wind damages were reported. Schools were closed at least three days and port operations in Chennai were suspended.


Early Hurricane Anais neared Madagascar on 14 October 2012
Early Hurricane Anais neared
Madagascar on 14 October 2012
Source: NASA Earth Observatory

In the Southwest Indian Ocean, the first tropical cyclone of the Southern Hemisphere's 2012/2013 hurricane season, Tropical Cyclone Anais (Oct 12th–19th) formed southwest of Diego Garcia and dissipated near the northeast coast of Madagascar without making landfall. Notably, the storm (equivalent to a Category 3 hurricane in the Atlantic Basin) was deemed as the strongest hurricane to occur so early in the season and the second earliest hurricane of any intensity, after Tropical Cyclone Blanche, which formed in October 1969, according to media accounts.

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Severe winter weather

Central European cyclone on 28 October 2012
Central European cyclone
on 28 October 2012
Source: Copyright 2012 EUMETSAT

Central and eastern Europe received heavy snow on October 28th. For several locations it marked an early, first snowfall of the season, according to media reports. Up to 40 cm (15.7 inches) of snow fell across the Alps mountain range. One person was injured in a traffic accident involving eight cars, which resulted in the closure of a road in Fribourg, Switzerland. In southern Poland, three persons perished due to frostbite as the heavy snow caused power outages for over 70,000 residents. Parts of Croatia received around 20 cm (7.9 inches) of snow. Fallen trees and wet snow blocked roads and delayed rail services in the Czech Republic. In Russia, the city of Moscow received up to 6 cm (2.4 inches). Strong southerly winds along Bulgaria's Black Sea coast forced closure of the ports in Varna and Burgas, while heavy rainfall occurred over the country's southern regions of Smolyan and Kardzhali.


Northeast China snow on 23 October 2012
Northeast China snow
on 23 October 2012
Source: NASA Earth Observatory

The previous week, areas of northeast China experienced the first snowfall of winter as well. A cold front stretching from Beijing to Harbin dropped temperatures, while snow caused closure of an expressway on October 22nd. Near Tianmen, one person was killed in the collapse of a structure during heavy rains in central China.


Rare snowfall in South Australia on 11 October 2012
Rare snowfall in South Australia
on 11 October 2012
Source: Australian Bureau of Meteorology

Passage of a very cold air-mass across the Mount Lofty and Flinders Ranges in South Australia produced an unseasonable snowfall in the town of Hallett on October 11th. Deemed as a once-in-a-century October snow event, the measurements varied from 34 mm (1.33 inches) to 8 mm (0.31 inch) around the area surrounding Adelaide (northwest to southeast), according to media reports. Strong southerly winds occurred on the Yorke Peninsula, along with heavy rain which felled power lines and signage that crushed a parked vehicle. Despite precipitation of close to 17 mm (0.65 inch) associated with the storm, Adelaide experienced its driest October in three years. Monthly rainfall was very much below average across the Adelaide region with many locations receiving less than half of the long-term October average.

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Polar Events and Sea Ice
Sea ice swirled off Greenland on 17 October 2012
Sea ice swirled off Greenland
on 17 October 2012
Source: NASA Earth Observatory

Remnants of Arctic sea ice that drifted along the east coast of Greenland in mid-October produced a pattern of swirls as viewed by satellite. The volume of Arctic ice has declined as the thickness of the ice decreased — a result of a lessening of multi-year ice.

Changes in Antarctic Rift from October to September 2012
Changes in Antarctic Rift from
October to September 2012
Source: NASA Earth Observatory

Over the past year, scientists continued to monitor cracks along the West Antarctic ice sheet. NASA has conducted annual airborne surveys of polar ice since 2009 as part of a six-year mission known as Operation IceBridge. A highly specialized fleet of research aircraft outfitted with a sophisticated suite of innovative science instruments collects data for studying changes in thickness of sea ice, glaciers, and ice sheets. A second crack developed in May 2012 alongside a massive rift that was initially detected in October 2011 on the Pine Island Glacier (PIG) ice shelf. The new iceberg, which will ultimately split from the PIG as the rift lengthens, is anticipated to be the largest in several decades.

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National Snow & Ice

NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.


Overview | Notable Events

Overview:

During October, several cold fronts moved through the Northern Plains and Rockies, providing the first seasonal snowfall across the region. A Pacific storm near mid-month dropped several feet of snow across the highest elevations of the Sierra Nevada Mountains, giving an early start to the snow season. The remnants of Hurricane Sandy brought record-breaking, early season snowfall along the highest elevations of the Appalachian Mountains at the end of the month.

Contiguous US snow cover anomalies
U.S. October Snow Cover Extent Anomalies
Source: Rutgers Global Snow Lab

At the beginning of October, snow covered zero percent of the contiguous United States. By the 26th, the snow cover expanded to a monthly maximum of 20.3 percent. On October 31st, snow was on the ground for 4.5 percent of the country — across the highest terrain in the West, in northern Minnesota, and along the Central and Southern Appalachians. For the month as a whole, the contiguous U.S. experienced below-average snow cover extent, according to Rutgers Global Snow Lab. The October monthly snow cover extent was 22,000 square miles (57,000 square km), 48,680 square miles (126,090 square km) below hte 1981-2010 average, and the 15th smallest October snow cover extent in the 45-year period of record. Below-average snow cover was observed across the Intermountain West, while above-average October snow cover occurred across the Central and Southern Appalachians.

Summary of Notable Snow Events:
Sandy Snowfall Totals
Sandy remnant-low snowfall totals

The remnant low pressure system from Hurricane Sandy dropped copious amounts of snow across the Southern and Central Appalachians as it moved westward after making landfall near Atlantic City, New Jersey on October 29th. Over a foot of snow was reported in six states from North Carolina to Pennsylvania, shattering October monthly snowfall records. Widespread, heavy snow of this magnitude during October has never been observed across this region. The largest snow totals occurred along the highest elevations of the Appalachians, with Mount Leconte, Tennessee receiving 33 inches of snow and Terra Alta, West Virginia measuring 36 inches. Very strong winds combined with the snow to create blizzard conditions for up to two days in some locations. The largest impacts of the storm were the massive power outages due to downed trees and power lines and building collapses because of the heavy, wet nature of the snow. Flooding was also a concern as warm temperatures returned quickly after the storm causing rapid melt and runoff.

Synoptic Discussion

Note: This Synoptic Discussion describes recent weather events and climate anomalies in relation to the phenomena that cause the weather. These phenomena include the jet stream, fronts and low pressure systems that bring precipitation, high pressure systems that bring dry weather, and the mechanisms which control these features — such as El Niño, La Niña, and other oceanic and atmospheric drivers (PNA, NAO, AO, and others). The report may contain more technical language than other components of the State of the Climate series.


NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.


Synoptic Discussion

Monthly upper-level circulation pattern and anomalies
Monthly upper-level circulation pattern and anomalies.

The weather patternweather pattern over North America during October 2012 consisted of the seasonal battle between subtropical high pressure (High, or upper-level ridge) to the south and the polar jet stream and associated storm track to the north. As the sun angle decreases during Northern Hemisphere autumn, polar air masses get colder and normally expand the polar jet toward the south. The jet stream was a little more active than seasonal normals this month, propagating numerous cool upper-level troughs into the contiguous U.S., with surface cold fronts and low pressure systems following in their wake. When averaged over the month, this pattern resulted in cooler-than-average temperatures beneath a stronger-than-average upper-level trough stretching from western Canada to the Southeast United States. The storm track directed weather systems into the Pacific Northwest, across the northern Plains and southern Canadian Prairies, then into the Great Lakes and Midwest. This jet stream pattern inhibited the formation of tornadoes and wildfires, both of which were below normal for October, and brought beneficial rainfall which improved drought conditions in the Midwest. It also brought snow to parts of the Northwest, Northern and Central Rockies, and adjoining parts of the Great Plains at mid-month. But, averaged over the month, above-normal upper-level geopotential heights and descending air ("subsidence") associated with the subtropical High reduced precipitation and kept temperatures above-normal over the Southwest. The October dry weather extended into the Central and Southern Plains, where the most intense drought continued its grip. Five tropical systems (two hurricanes and three tropical storms) formed in the Atlantic basin during October, well above the long-term average. The overall circulation pattern normally deflects such coastal systems further out into the Atlantic. But for Hurricane Sandy, which wrought devastation in the Caribbean and western North Atlantic islands before moving up the eastern U.S. seaboard, an unusual upper-level jet stream flow pulled it into the northeastern U.S., where it combined with a cold front to cause locally heavy rain, strong winds, widespread flooding, and — in the central Appalachiansareas of heavy snow.

The movement of several weather systems — wet low pressure over the Southeast at the beginning of the month, an upper-level low with rainfall over the Southwest early in the month, fronts across the northern states later in the month, and the remains of Sandy in the Northeast at the end of the month — can be seen in the weekly above-normal precipitation anomaly patterns (weeks 1, 2, 3, 4, 5). Areas of persistent dryness, especially across parts of the Plains, are also evident. Nine states (mostly in the Southwest and Southern to Central Plains) ranked in the driest third of the historical record, with Texas having the ninth driest October in the 1895-2012 record. Twenty-three northern tier and Midwest states ranked in the wettest third of the historical record, with seven of them in the top ten category and Delaware ranking wettest on record for October. According to the end-of-October (October 30) U.S. Drought Monitor, 60.2% of the contiguous U.S. (50.4% of the U.S. including Alaska, Hawaii, and Puerto Rico) was affected by moderate to exceptional drought overall. These values are lower than those at the end of September, reflecting improvement in the Northeast, Mid-Atlantic, Midwest, and parts of the Northern Plains. According to the Palmer Drought Index, which goes back to the beginning of the 20th century, 49.2% of the contiguous U.S. was in moderate to extreme drought, a decrease of about 3 percent compared to last month. The 2012 Palmer Drought Index percent area values have been exceeded only by the droughts of the 1930s and 1950s.

The movement of the cool fronts can be seen in the weekly temperature anomaly maps (weeks 1, 2, 3, 4, 5). The persistence of warm anomalies in the Northeast, and frequent excursions of cool air masses — especially east of the Rockies — gave 19 states, from Montana to Alabama, monthly temperature ranks in the coolest third of the historical record, and 14 states, split between the Northeast and Southwest, monthly temperature ranks in the warmest third of the historical record. On a local basis, there were more record cold highs and lows than record warm highs and lows, which is a change from the last several months where warm records dominated over cool records. About 1300 record low temperatures and 2400 record cool daily high temperatures were tied or broken. In comparison, a little over 900 daily high temperature records and about 2350 record warm daily low temperatures were tied or broken. (These numbers are preliminary and are expected to increase as more data arrive.) On balance, the warm and cold anomalies, combined with the time of year, contributed to a national Residential Energy Demand Temperature Index (REDTI) for October 2012 that was near average.

When averaged together, the mixture of temperature and precipitation extremes gave the U.S. the 44th coolest and 52nd wettest October in the 118-year record. Averaging extremes tends to cancel them out (as is the case for this month). But when extremes are combined cumulatively, like in the U.S. Climate Extremes Index (USCEI), they may tell a different story. Nationally, the large spatial extent of very dry conditions ranked the PDSI component fourth largest for October 2012 (behind October 1934, 1956, and 1954) and the number of days with extreme precipitation component ranked 14th largest for October 2012, but the other components ranked low or mid-range, giving the U.S. an October USCEI that ranked only 39th largest. Even with Sandy (tropical cyclone component) considered, the national October USCEI still ranked only 34th largest. However, the preponderance of unusual warmth and dryness for much of 2012 has ranked the national USCEI largest for the year-to-date (January-October) and second largest for the last twelve months (November-October).

Subtropical highs, and cold fronts and low pressure systems moving in the storm track flow, are influenced by the broadscale atmospheric circulation. Five such large-scale atmospheric circulation drivers were potentially influential during October:

Map of monthly temperature anomalies Map of monthly precipitation anomalies

Upper-level circulation pattern and anomalies averaged for the last three months
Upper-level circulation pattern and anomalies averaged for the last three months.

Examination of these circulation indices and their teleconnection patterns, and comparison to observed October and August-October 2012 temperature, precipitation, and circulation patterns, suggests that ENSO, PNA, and NAO had little influence on the observed weather patterns, but the teleconnections are weak this time of year for the PNA, AO, and NAO. The AO and EP-NP may have exerted some influence on the weather this past month and season. The temperature patterns over the last three months, especially the frequent movement of cold fronts across the U.S. east of the Rockies, and upper-level circulation patterns reasonably reflect a positive EP-NP. The temperature patterns could reflect the negative AO and NAO teleconnections — if it were winter. As noted above, some of the indices have weak teleconnections in the fall, so it appears that the EP-NP pattern dominated. When the atmospheric circulation drivers are neutral or in a state of transition, their influence becomes difficult to trace and can be overwhelmed by other competing forces, including random fluctuations in the atmosphere. But even when the atmospheric drivers are strong, their influence can be masked by short-term fluctuations like the highly unusual occurrence of Sandy.

Tornadoes

NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.


According to data from NOAA's Storm Prediction Center, during October, there were 41 preliminary tornado reports. This is slightly less than the 1991-2000 October average of 61 tornadoes. Tornado activity during October and autumn in general, varies from year to year. The most active October occurred in 2001 when 119 tornadoes impacted the nation and the least active October occurred in 1952 when no tornadoes impacted the United States. Despite the slow tornado activity, two unusual tornado outbreaks did impact the country — one in the Southeast on October 17th and one in California on October 22nd.

October 2012 Tornadoes Year-to-date
January-October Tornado Counts

The below-average tornado activity during October continued a slower-than-average tornado year across the country. The preliminary number of tornadoes during the January-October period was 900, with 138 tornado reports still pending for August, September, and October. This marked the lowest January-October tornado count since 2002.

October 17 2012 Tornadoes
17 October Tornado Reports

A strong, fast moving storm system moved through the Southeast on October 17th spawning 15 preliminary reports of tornadoes across Mississippi and Arkansas, with central Mississippi receiving the brunt of the action. Tornado activity this time of year across Mississippi is unusual, with the state averaging three tornadoes during October. A confirmed EF-3 tornado tracked over 16 miles through Scott and Newton counties, injuring one person. This marks only the second EF-3 tornado on record for the state during October. Two additional EF-2 tornadoes were confirmed, bringing the count of strong (EF-2+) tornadoes to three. This marks the second most number of strong tornadoes to impact Mississippi during October on record, and the 11 confirmed total ties the largest October outbreak on record for the state. During the entire outbreak, there were four injuries and no reported fatalities.

October 22 2012 Tornadoes
22 October Tornado Reports in California

On October 22nd a strong Pacific storm system moved through Northern California, causing damaging winds and at least five confirmed tornadoes around the Sacramento area. According to the National Weather Service assessment, this tied a 1996 single-day tornado record for this region of California. The entire state averages 11 tornadoes annually and less than one tornado during the month of October. Dozens of homes and businesses were damaged in California’s Central Valley during the severe weather outbreak, but no injuries or fatalities were reported. The tornadoes were all weak in nature, rated either EF-1 or EF-0. The storm system also caused early-season heavy snowfall across the Sierra Nevada.

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Hurricanes & Tropical Storms

NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.


Note: This report catalogs recent tropical cyclones and places each basin's tropical cyclone activity in a climate-scale context. It is not updated in real time. Users seeking real time status and forecasts of tropical cyclones should visit The National Hurricane Center.

West North Pacific Basin

Maliksi
Tropical Storm Maliksi Satellite Image
Maliksi Track
Tropical Storm Maliksi Forecast Track


Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Maliksi
Cyclogenesis Date 10/01
Cyclolysis Date 10/05
Highest Saffir-Simpson Category TS
Maximum 6-hr Sustained Wind 52 mph (45 kt or 83 km/h)
Min Pressure 985 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) 2.7500 x 104
Landfall Information (date, location and sustained winds)
Deaths
*The (ACE) Index calculations are based on preliminary data.

Gaemi
Tropical Storm Gaemi Satellite Image
Gaemi Track
Tropical Storm Gaemi Forecast Track


Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Gaemi(Marce)
Cyclogenesis Date 10/01
Cyclolysis Date 10/06
Highest Saffir-Simpson Category TS
Maximum 6-hr Sustained Wind 63 mph (55 kt or 102 km/h)
Min Pressure 990 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) 3.4500 x 104
Landfall Information (date, location and sustained winds)
Deaths
*The (ACE) Index calculations are based on preliminary data.

Prapiroon
Tropical Storm Prapiroon Satellite Image
Prapiroon Track
Tropical Storm Prapiroon Forecast Track


Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Prapiroon(Nina)
Cyclogenesis Date 10/07
Cyclolysis Date 10/19
Highest Saffir-Simpson Category Cat 3
Maximum 6-hr Sustained Wind 115 mph (100 kt or 185 km/h)
Min Pressure 940 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) 22.5750 x 104
Landfall Information (date, location and sustained winds)
Deaths
*The (ACE) Index calculations are based on preliminary data.

Maria
Tropical Storm Maria Satellite Image
Maria Track
Tropical Storm Maria Forecast Track


Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Maria
Cyclogenesis Date 10/07
Cyclolysis Date 10/20
Highest Saffir-Simpson Category TS
Maximum 6-hr Sustained Wind 63 mph (55 kt or 102 km/h)
Min Pressure 990 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) 3.9675 x 104
Landfall Information (date, location and sustained winds)
Deaths
*The (ACE) Index calculations are based on preliminary data.

Ofel
Tropical Storm Ofel Satellite Image
Ofel Track
Tropical Storm Ofel Forecast Track


Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Ofel(Son-Tinh)
Cyclogenesis Date 10/24
Cyclolysis Date 10/29
Highest Saffir-Simpson Category Cat 3
Maximum 6-hr Sustained Wind 127 mph (110 kt or 204 km/h)
Min Pressure 945 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) 9.9150 x 104
Landfall Information (date, location and sustained winds) 10/24 - Philippines (35 kt or 65 km/h)
10/28 - Vietnam (75 kt or 139 km/h)
Deaths 39
*The (ACE) Index calculations are based on preliminary data.

Atlantic Basin

Oscar
Tropical Storm Oscar Satellite Image


Oscar Track
Tropical Storm Oscar Track


Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Oscar
Cyclogenesis Date 10/04
Cyclolysis Date 10/05
Highest Saffir-Simpson Category TS
Maximum 6-hr Sustained Wind 52 mph (45 kt or 83 km/h)
Min Pressure 997 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) .9700 x 104
Landfall Information (date, location and sustained winds)
Deaths 0
*The (ACE) Index calculations are based on preliminary data.

Patty
Tropical Storm Patty Satellite Image


Patty Track
Tropical Storm Patty Track

Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Patty
Cyclogenesis Date 10/11
Cyclolysis Date 10/12
Highest Saffir-Simpson Category TS
Maximum 6-hr Sustained Wind 46 mph (40 kt or 74 km/h)
Min Pressure 1005 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) .6500 x 104
Landfall Information (date, location and sustained winds)
Deaths 0
*The (ACE) Index calculations are based on preliminary data.

Rafael
Tropical Storm Rafael Satellite Image


Rafael Track
Tropical Storm Rafael Track

Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Rafael
Cyclogenesis Date 10/13
Cyclolysis Date 10/17
Highest Saffir-Simpson Category Cat 1
Maximum 6-hr Sustained Wind 86 mph (75 kt or 139 km/h)
Min Pressure 969 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) 6.9975 x 104
Landfall Information (date, location and sustained winds)
Deaths 1
*The (ACE) Index calculations are based on preliminary data.

Sandy
Tropical Storm Sandy Satellite Image


Sandy Track
Tropical Storm Sandy Track

Safir Simpson Color Legend for Track Map from Unisys
Saffir-Simpson Scale Color Legend
Tropical Cyclone Summary
Tropical Cyclone Sandy
Cyclogenesis Date 10/23
Cyclolysis Date 10/30
Highest Saffir-Simpson Category Cat 2
Maximum 6-hr Sustained Wind 105 mph (95 kt or 176 km/h)
Min Pressure 940 mbar
Accumulated Cyclone Energy (ACE*) Index (kt2) 14.2150 x 104
Landfall Information (date, location and sustained winds) 10/24 - Jamaica (70 kt or 130 km/h)
10/25 - Cuba (95 kt or 176 km/h)
10/29 - coastal New Jersey (80 kt or 148 km/h)
Deaths 165
*The (ACE) Index calculations are based on preliminary data.

The tropical storm which would develop into Hurricane Sandy formed in the Caribbean Sea, just south of Jamaica on October 22nd. Sandy moved northward, strengthening into a category 1 hurricane before making landfall along Jamaica’s southern coast. Hurricane Sandy continued its northward track across Cuba and the Bahamas through the 25th when the storm’s intensity peaked at Category 2 strength, with sustained winds of 105 miles per hour. Sandy moved parallel to the Eastern Seaboard of the U.S. where it weakened to Category 1 strength. On October 28th, tropical storm force winds reached the North Carolina coast. On the 29th, an upper level trough positioned over the eastern U.S. became negatively tilted (oriented from Northwest to Southeast), steering the storm directly towards the New Jersey Coast, an unusual tropical cyclone track. Warmer-than-average sea surface temperatures (3-5°F above average) allowed Sandy to retain tropical characteristics much farther north than what is typical this late in the North Atlantic Hurricane Season. Hours before landfall, Sandy began to lose tropical characteristics, and the storm hit near Atlantic City, New Jersey as it was transitioning from a tropical cyclone to an extra-tropical cyclone. At landfall, post-tropical storm Sandy had a central minimum pressure of 946 millibars and sustained winds of 80 miles per hour with tropical storm force winds extending up to 500 miles from the center of the storm.

At the time this report was published, it was known that Sandy had caused numerous fatalities across the Caribbean early in its life — 54 fatalities in Haiti, 11 in Cuba, 2 in both the Bahamas and Dominican Republic, and 1 in Jamaica. Impacts across the U.S. included record breaking storm surge for the densely populated Northeast Corridor, widespread wind damage, coastal and inland flooding, blizzard conditions for the Appalachians, and power outages to over 8 million households. Over 100 fatalities were confirmed due to Sandy in the U.S., mostly in New Jersey and New York. More information on the impacts of Sandy and records broken due to the storm in the U.S. can be found here:

  • Sandy Precipitation
  • Sandy Wind and Storm Surge
  • Sandy Barometric Pressure Records

  • Tony
    Tropical Storm Tony Satellite Image


    Tony Track
    Tropical Storm Tony Track

    Safir Simpson Color Legend for Track Map from Unisys
    Saffir-Simpson Scale Color Legend
    Tropical Cyclone Summary
    Tropical Cyclone Tony
    Cyclogenesis Date 10/24
    Cyclolysis Date 10/25
    Highest Saffir-Simpson Category TS
    Maximum 6-hr Sustained Wind 52 mph (45 kt or 83 km/h)
    Min Pressure 1000 mbar
    Accumulated Cyclone Energy (ACE*) Index (kt2) 1.3750 x 104
    Landfall Information (date, location and sustained winds)
    Deaths 0
    *The (ACE) Index calculations are based on preliminary data.

    East North Pacific Basin

    Olivia
    Tropical Storm Olivia Satellite Image
    Olivia Track
    Tropical Storm Olivia Forecast Track


    Safir Simpson Color Legend for Track Map from Unisys
    Saffir-Simpson Scale Color Legend
    Tropical Cyclone Summary
    Tropical Cyclone Olivia
    Cyclogenesis Date 10/06
    Cyclolysis Date 10/08
    Highest Saffir-Simpson Category TS
    Maximum 6-hr Sustained Wind 58 mph (50 kt or 93 km/h)
    Min Pressure 998 mbar
    Accumulated Cyclone Energy (ACE*) Index (kt2) 1.9850 x 104
    Landfall Information (date, location and sustained winds)
    Deaths
    *The (ACE) Index calculations are based on preliminary data.

    Paul
    Tropical Storm Paul Satellite Image
    Paul Track
    Tropical Storm Paul Forecast Track


    Safir Simpson Color Legend for Track Map from Unisys
    Saffir-Simpson Scale Color Legend
    Tropical Cyclone Summary
    Tropical Cyclone Paul
    Cyclogenesis Date 10/14
    Cyclolysis Date 10/17
    Highest Saffir-Simpson Category Cat 3
    Maximum 6-hr Sustained Wind 115 mph (100 kt or 185 km/h)
    Min Pressure 960 mbar
    Accumulated Cyclone Energy (ACE*) Index (kt2) 6.9825 x 104
    Landfall Information (date, location and sustained winds)
    Deaths
    *The (ACE) Index calculations are based on preliminary data.

    Rosa
    Tropical Storm Rosa Satellite Image
    Rosa Track
    Tropical Storm Rosa Forecast Track


    Safir Simpson Color Legend for Track Map from Unisys
    Saffir-Simpson Scale Color Legend
    Tropical Cyclone Summary
    Tropical Cyclone Rosa
    Cyclogenesis Date 10/30
    Cyclolysis Date Active
    Highest Saffir-Simpson Category TS
    Maximum 6-hr Sustained Wind 58 mph (50 kt or 93 km/h)
    Min Pressure 1000 mbar
    Accumulated Cyclone Energy (ACE*) Index (kt2) N/A
    Landfall Information (date, location and sustained winds)
    Deaths
    *The (ACE) Index calculations are based on preliminary data.

    North Indian Basin

    Murjan
    Tropical Storm Murjan Satellite Image
    Murjan Track
    Tropical Storm Murjan Forecast Track


    Safir Simpson Color Legend for Track Map from Unisys
    Saffir-Simpson Scale Color Legend
    Tropical Cyclone Summary
    Tropical Cyclone Murjan
    Cyclogenesis Date 10/24
    Cyclolysis Date 10/25
    Highest Saffir-Simpson Category TS
    Maximum 6-hr Sustained Wind 40 mph (35 kt or 65 km/h)
    Min Pressure 1000 mbar
    Accumulated Cyclone Energy (ACE*) Index (kt2) .6125 x 104
    Landfall Information (date, location and sustained winds)
    Deaths
    *The (ACE) Index calculations are based on preliminary data.

    Nilam
    Tropical Storm Nilam Satellite Image
    Nilam Track
    Tropical Storm Nilam Forecast Track


    Safir Simpson Color Legend for Track Map from Unisys
    Saffir-Simpson Scale Color Legend
    Tropical Cyclone Summary
    Tropical Cyclone Nilam
    Cyclogenesis Date 10/29
    Cyclolysis Date Active
    Highest Saffir-Simpson Category TS
    Maximum 6-hr Sustained Wind 63 mph (55 kt or 102 km/h)
    Min Pressure 992 mbar
    Accumulated Cyclone Energy (ACE*) Index (kt2) 2.0600 x 104
    Landfall Information (date, location and sustained winds)
    Deaths
    *The (ACE) Index calculations are based on preliminary data.

    Drought

    NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.

    Issued 15 November 2012
    Contents Of This Report:
    Map showing Palmer Z Index

    National Drought Overview

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    Detailed Drought Discussion

    Overview

    October 2012 marked a departure from the warmth of the last 16 months, averaging cooler than normal (44th coolest October on record, based on data back to 1895) with near-average precipitation (52nd wettest October), when weather conditions are averaged across the country. Like the last couple months, cool fronts swept across the country (weeks 1, 2, 3, 4, 5), but this time the monthly temperature pattern had below-normal temperatures covering more of the country — stretching from Montana to Alabama. High pressure (High, or upper-level ridge), with its descending air ("subsidence"), dominated the Southwest, resulting in a monthly pattern of anomalous warmth there with below-normal precipitation which stretched into the Central and Southern Plains. The Northeast was dominated by warmer-than-normal temperatures and, for most of the month, dry weather. The storm track kept above-normal precipitation mainly across the northern states and Midwest, with the remnants of Hurricane Sandy combining with a cold front to bring wet conditions to the Northeast at the end of the month (weeks 1, 2, 3, 4, 5). The wet weather improved drought conditions in the Midwest and virtually eliminated them in the Northeast, but dry weather helped intense drought keep its grip across much of the Plains, West, and Hawaii. Nationally, the moderate-to-exceptional (D1-D4) drought footprint decreased to about 50 percent of the country, compared to last month, while the percentage in the abnormally dry to exceptional drought category decreased to about 66 percent. About 16 percent of the country was in the worst drought categories (D3-D4, extreme to exceptional drought), a bit less than last month. The Palmer Drought Index, whose data go back 113 years, is relied upon for drought comparisons before 2000. The October 2012 Palmer value of 49 percent in moderate to extreme drought is a decrease of about 3 percent compared to last month, and the percent area in severe to extreme drought decreased to about 34 percent.

    The U.S. Drought Monitor drought map valid October 30, 2012
    The U.S. Drought Monitor drought map valid October 30, 2012.

    By the end of the month, the core drought areas in the U.S. included:


    Palmer Drought Index

    The Palmer drought indices measure the balance between moisture demand (evapotranspiration driven by temperature) and moisture supply (precipitation). The Palmer Z Index depicts moisture conditions for the current month, while the Palmer Hydrological Drought Index (PHDI) and Palmer Drought Severity Index (PDSI) depict the current month's cumulative moisture conditions integrated over the last several months.

    Palmer Z Index map Palmer Hydrological Drought Index map

    Used together, the Palmer Z Index and PHDI maps show that some long-term drought areas (north and Midwest) received short-term relief, while for other areas (Southwest, Southeast, and Southern Plains), short-term dry conditions exacerbated long-term drought. Precipitation from frontal systems along the Pacific Northwest to Northern Plains nibbled at the northern edge of the nation's drought area, while rain from Midwest fronts and the Sandy system cut away at the drought area from the east (October PHDI compared to September PHDI). Above-normal precipitation from these systems, as well as the massive area of below-normal temperatures (which reduced evapotranspiration), contributed to a reduced area of short-term drought (as seen on the Palmer Z Index map). But long-term drought intensified (October PHDI compared to September PHDI) over the Southwest and Southern Plains where the Palmer Z Index map showed short-term drought due to warmer- and drier-than-normal October conditions.


    Standardized Precipitation Index

    The Standardized Precipitation Index (SPI) measures moisture supply. The SPI maps here show the spatial extent of anomalously wet and dry areas at time scales ranging from 1 month to 24 months.

    1-month Standardized Precipitation Index 2-month Standardized Precipitation Index 3-month Standardized Precipitation Index

    The 1-month SPI shows the main area of dryness extending from the Southwest and Central Rockies to the Southern and Central Plains, with another dry area centered in the Southeast. At 2 to 3 months, the epicenter of dryness shifts to the Central Plains, Upper Midwest, Intermountain Basin, and up and down the Rockies. The 6- to 9-month SPI maps have dryness expanded into the Ohio Valley and further in the West. At 12 months, dryness is generally oriented from the Southwest to Central and Northern Plains, with some dry areas in the Upper Midwest. Dryness at 24 months is mostly concentrated in the central and southern portions of the Plains and Rockies. The Southeast is dry at virtually all time scales, but the dryness is most severe at 24 months. For the Central Plains and Rockies, the dryness is most severe at 3 to 12 months.

    On the other (wet) side of the coin, wet conditions are evident at 1 month from the Pacific Northwest to extreme Northern Plains and from 1 to 6 months and at 24 months for the Northeast. The Midwest shows recent wetness (1-3 months), intermediate dryness (6-12 months), and longer-term wet conditions (24 months). Parts of the Deep South (mainly Gulf coast) are wet on the 3- to 12-month SPI maps, while the Pacific Northwest is generally wet from 6 to 12 months.


    6-month Standardized Precipitation Index 12-month Standardized Precipitation Index 24-month Standardized Precipitation Index


    Agricultural and Hydrological Indices and Impacts

    USDA topsoil moisture short to very short
    USDA topsoil moisture short to very short
    USGS monthly streamflow percentiles
    USGS monthly streamflow percentiles

    Drought conditions were reflected in numerous agricultural, hydrological, and other meteorological indicators, both observed and modeled.

    Agricultural:

    Based on end-of-October (October 31st) USDA reports, 54 percent of the nation's pasture and rangeland was rated in poor to very poor condition. Several states, from California to the Central Plains, had 80 percent or more of their pasture and rangeland rated poor to very poor, with virtually all of it so rated in Nebraska and California. Winter wheat emergence was hampered by drought in several central and northwestern states, with 65 percent of the winter wheat in drought. Overall, 15 percent of the winter wheat was rated in poor to very poor condition, although that number was much higher in South Dakota (61 percent) and Nebraska (49 percent). Topsoil moisture has recovered where precipitation has fallen (October 28 compared to September 30), but conditions are still very dry where it hasn't. More than 90 percent of the topsoil was rated short or very short of moisture in New Mexico and Nebraska, and over 70 percent so rated in Wyoming, Colorado, Oklahoma, and even Georgia.

    Map showing USDA pasture and rangeland conditions
    Map showing USDA pasture and rangeland conditions.

    Hydrological:

    USGS groundwater percentile map
    USGS groundwater percentile map.

    Meteorological:

    Map showing number of days with precipitation
    Map showing number of days with precipitation.


    Regional Discussion

    Hawaii: October 2012 was a very dry month for the Hawaiian Islands. The pattern of below-normal rainfall was evident at most time periods (last 2, 3, 6, 12, 24, and 36 months), especially for the southern islands, and streamflow was below normal for most of the islands. Moderate to extreme drought affected 52 percent of the state, a little more than last month.

    Alaska: It was drier than normal in the southeast and along the southern coast, but wetter than normal at most interior and northern stations, during October 2012. A pattern of dryness extends from the southeast panhandle to interior southeast stations at 2 and 3 months, with some hint of that pattern continuing at the longer time scales (6, 12, 24, and 36 months). An area of abnormal dryness covered the northern areas on the USDM map.

    Puerto Rico: The south central and southeast coastal areas and central region of the island were drier than normal this month. Above-normal rainfall over other parts of the island helped bring the monthly streamflow back to near normal levels. But the October rainfall was not enough to make up for earlier precipitation deficits. A dry band stretched across the southern and central portions of Puerto Rico at 2, 3, and 6 months, with the southeast dry for the year to date. The October 30th USDM map was free of any drought or abnormally dry areas.

    CONUS State Ranks:

    Current month state precipitation ranks Texas statewide precipitation, October, 1895-2012

    Only about five percent of the U.S. was very dry (the driest ten percent of the historical record) during October 2012. This stands in marked contrast to the previous five months when up to a third of the country was very dry. On a statewide basis, October 2012 ranked in the driest third of the historical record for Octobers for nine states — mostly in the Southwest and Southern to Central Plains — with Texas having the ninth driest October in the 1895-2012 record.

    3-month state precipitation ranks 6-month state precipitation ranks

    Nebraska statewide precipitation, May-October, 1895-2012
    Nebraska statewide precipitation, May-October, 1895-2012.

    The spatial pattern of dryness at the three month time scale was centered in the Central to Northern Plains. Nebraska and Wyoming had the driest August-October in the historical record, followed by Minnesota (second driest) and South Dakota (fourth driest). In total, 14 states, mostly in the Rockies and Great Plains, ranked in the driest third of the historical record. A similar spatial pattern of dryness is evident at the six month time scale, except it extended farther east into the Ohio Valley. Again, Nebraska and Wyoming had the driest May-October on record, with six other states ranking in the top ten driest (Kansas (second driest), Oklahoma (fourth driest), South Dakota (fourth driest), Iowa (fifth driest), Missouri (fifth driest), and Colorado (sixth driest)). In fact, Nebraska had the driest July-October and June-October as well, and Wyoming also had the driest June-October. Eleven additional states ranked in the driest third of the historical record.

    year-to-date state precipitation ranks 12-month state precipitation ranks

    Wyoming statewide precipitation, January-October, 1895-2012
    Wyoming statewide precipitation, January-October, 1895-2012.

    For the year-to-date, the 3- and 6-month spatial pattern is evident — plus dryness in the Southeast shows up. Nebraska and Wyoming ranked driest for January-October 2012, and four other states ranked in the top ten driest category [Colorado (third driest), New Mexico (sixth driest), Iowa (seventh driest), and Kansas (tenth driest)]. Sixteen other states ranked in the driest third of the historical record, including Georgia (17th driest) and South Carolina (31st driest). At the 12-month time scale, dryness dominated from the West to the Midwest, with pockets of dryness in the Southeast and coastal Mid-Atlantic. November 2011-October 2012 ranked in the top ten driest category for five states, with 14 other states ranking in the driest third of the historical record. Again, Nebraska and Wyoming had the driest November-October on record, followed by Colorado at third driest, Utah at sixth driest, and South Dakota at seventh driest. The dryness in the Central Plains and Central Rockies was so severe and persistent this year that both Nebraska and Wyoming had the driest period on record in 2012 for all periods from the last six months (May-October) through the last twelve months (November-October). Not only was 2012 record-breaking, but Wyoming shows evidence of a long-term drying trend over the last hundred years.

    Nebraska statewide Palmer Drought Severity Index, January 1900-October 2012 Wyoming statewide Palmer Drought Severity Index, January 1900-October 2012

    The combination of well-above normal temperatures and well-below normal precipitation brought the PDSI to very low levels in the core drought area this summer, although it did not reach record low levels on a statewide basis. In 2012, Nebraska's PDSI fell to the lowest values since the 1950s, while Wyoming's rivaled the record low set in 2002. Colorado's PDSI suggested that the 2012 drought episode was the third worst episode after 2002 and 1934. New Mexico's was a continuation of last year which, together, rival the record 1950s drought. In South Dakota, the recent dryness lowered the 2012 PDSI to the most severe level since the 1930s, but this bucked a trend toward wet conditions for the last couple decades.


    Winter Wheat Belt:


    Primary Hard Red Winter Wheat agricultural belt precipitation, April-October, 1895-2012
    Primary Hard Red Winter Wheat agricultural belt precipitation, April-October, 1895-2012.

    As noted earlier, 15 percent of the winter wheat crop was rated in poor to very poor condition. Although October precipitation for the Winter Wheat agricultural belt was near average regionally (with October 2012 ranking 51st driest), the preceding months have been quite dry (April-October 2012 ranked as the fourth driest such period in the 1895-2012 record), thus drying out soils going into the winter wheat growing season (which begins in October). Conditions were even drier in the smaller Primary Hard Red Winter Wheat belt, with October 2012 ranking 20th driest and April-October 2012 ranking second driest (behind 1956). With April-October 2011 ranking eighth driest, the last two years have severely depleted the soil moisture in this area. The aggregate PDSI for the Primary Hard Red Winter Wheat area reached the lowest value since the 1950s, while the PDSI for the broader Winter Wheat area was far less extreme since this larger area encompassed counties that have seen wetter conditions recently. For comparison, the PDSI for the Spring Wheat belt (map) dropped from record wet only a few months ago to the driest since 1988, and similarly for the Primary Corn and Soybean belt.


    River Basins:


    Great Lakes Basin temperature, November-October, 1895-2012
    Great Lakes Basin temperature, November-October, 1895-2012.

    According to the U.S. Army Corps of Engineers, monthly lake-wide mean levels on Lakes Michigan, Huron, and Superior were near record lows during the month of October. Drought has affected parts of the Great Lakes during 2012; however, it was not as severe as in the Midwest and Great Plains. For example, the last twelve months (November 2011-October 2012) for the U.S. climate divisions surrounding Lake Superior was slightly drier than normal, which would not account for such low lake levels. But November 2011-October 2012 was the warmest such period in the 1895-2012 record. Persistent warmth for most of the last two decades, with the accompanying above-normal evaporation, could be a factor in the low lake levels. The entire Great Lakes Basin had the warmest November-October on record this year and the last couple of decades have been persistently warmer than normal, but precipitation basin-wide has been on the wet side in recent decades.

    The PDSI for the Great Lakes Basin was only slightly negative this summer. For other basins (such as the Rio Grande and Upper Mississippi basins), the PDSI was nowhere near a record. But for others (such as the Missouri and Upper Colorado basins), the 2012 drought approached previous records. And for the much bigger Mississippi River and its tributaries north of Memphis, Tennessee, into which the Missouri and Ohio rivers flow, drought was beginning to show up in 2012.

    Western U.S.


    Percent area of the Western U.S. in moderate to extreme drought, based on the Palmer Drought Index
    Percent area of the Western U.S. in moderate to extreme drought, based on the Palmer Drought Index.

    Beneficial precipitation fell in the northern parts of the West this month, relieving moisture stress that had developed during the previous two months. But for much of the rest of the West, October 2012 was drier than normal, as seen in data from both the low elevation stations and high elevation (SNOTEL) stations. The Southwest was especially afflicted with short-term drought this month due to the combination of below-normal precipitation and above-normal temperatures (which increased evapotranspiration). Some of the October precipitation fell as snow, with snow water equivalent percentile and percent of normal values relatively high, especially in the north, but this is due largely to snow depth normals being low this early in the season. Reservoir storage was below average, statewide, in most of the western states, but near to slightly above average in Montana and Washington where beneficial precipitation has fallen. According to the USDM, 76 percent of the West was experiencing moderate to exceptional drought at the end of October, a one percent increase compared to September. The Palmer Drought Index percent area statistic was about 63 percent, a ten percent jump compared to last month.


    NOAA Regional Climate Centers:


    A more detailed drought discussion, provided by the NOAA Regional Climate Centers and others, can be found below.

    SoutheastSouthMidwestNortheastHigh Plains
    WestUpper Colorado River BasinPacific Islands

    As described by the High Plains Regional Climate Center, October 2012 was cooler than normal for the majority of the region. Ample precipitation was confined to North Dakota and small pockets elsewhere in the High Plains region this month. Much needed precipitation fell in areas of northern North Dakota, where precipitation totals were over 150 percent of normal. While this precipitation was not record-breaking, it did help alleviate drought conditions there. A large portion of the region continued to have dry conditions this month. Central Nebraska, central South Dakota, southern Kansas, southern and northwestern Colorado, and south-central Wyoming all had precipitation totals which were less than 25 percent of normal. The dry weather helped with the harvesting of row crops in many areas across the region. The corn harvest was ahead of average in Kansas, Nebraska, North Dakota, and South Dakota. The soybean harvest was also well ahead of average in Nebraska, North Dakota, and South Dakota. On the downside, dryness continued to affect pasturelands as most of the region continued to have pasture conditions in the very poor to poor classifications. Dry and windy conditions also took their toll on winter wheat progress. For instance, the lack of precipitation limited winter wheat emergence in parts of South Dakota and some winter wheat had to be reseeded in Nebraska due to wind damage. Although mid-October showers did help with winter wheat emergence, according to the National Agricultural Statistics Service (NASS), more precipitation is needed for improved emergence.

    Slight changes in drought conditions in the High Plains region occurred over the past month, according to the USDM. Some areas experienced improvements and others had degradation which balanced out to little change over the past month. Nebraska was still the hardest hit state, with nearly 78 percent of the state in exceptional drought conditions (D4) which was up a few percent from the end of last month. South Dakota had the most degradation with a significant increase in D4 that went from 7 to 33 percent coverage over the past month. The most significant improvements occurred in the Red River Valley of North Dakota where precipitation in the middle of the month helped downgrade all extreme drought conditions (D3) to severe drought conditions (D2) in the state. Other areas which had improvements included north central Colorado, eastern Kansas, far southeastern Nebraska, and central North Dakota.

    Even with the growing season coming to a close, the ongoing drought has continued to have impacts across the region. The combination of an intense low pressure system to the east and high pressure over the Rockies created very strong northwest winds over the High Plains region October 17-18. The strongest wind speeds occurred on the 18th when winds were sustained at 35-45 mph (56-72 km/h) for much of the day. Gusts to 50-60 mph (80-97 km/h) were quite common and some peak wind gusts topping 70 mph (113 km/h) were reported as well. The combination of these winds and dry conditions from the ongoing drought caused a large dust storm to form. The dust storm reduced visibilities and many roads were forced to close, including portions of I-80 in western Nebraska and eastern Wyoming, I-70 in eastern Colorado, and I-35 in Kansas and Oklahoma. Unfortunately, wildfires also started during this time period and spread rapidly. According to NASS, in Nebraska, buildings, machinery, and even crops were lost in these fires. Impacts ranging from overturned semi-trucks to downed power lines to roof and tree damage were reported all across the wind swept region.

    As explained by the Southern Regional Climate Center, October was a slightly cooler than normal month for much of the Southern region. With the exception of Tennessee and northern Mississippi, October was much drier than normal month in the Southern region. A large portion of the region, including Oklahoma, Texas, Louisiana and southern Mississippi, received approximately half the normal amount of precipitation or less. Conditions were extremely dry throughout much of northwestern Texas and central Oklahoma, with many stations receiving only 5 to 25 percent of normal precipitation. Texas averaged only 0.83 inch (21.08 mm) of precipitation, making it their ninth driest October on record (1895-2012). The state of Oklahoma averaged 1.28 inches (32.51 mm), which is their twentieth driest October on record (1895-2012). Louisiana experienced its thirty-sixth driest October on record (1895-2012) with a state average precipitation of 1.83 inches (46.48 mm). Conversely, conditions were wetter than normal in Tennessee. The state averaged 4.03 inches (102.40 mm), making it their twenty-fourth wettest October (1895-2012). Other state average precipitation values include Mississippi, which averaged 3.56 inches (90.42 mm), and Arkansas, which averaged 3.33 inches (84.58 mm). Despite widespread dryness in October over much of the Southern region, drought conditions have not changed significantly over the past month. Slight improvements occurred in western Tennessee and in northern Mississippi. There was also a one category improvement in northern Arkansas, which improved from exceptional drought to severe and extreme drought. Elsewhere, conditions remained relatively unchanged.

    As summarized by the Midwest Regional Climate Center, October temperatures in the Midwest were below normal for the second straight month. Statewide October temperatures ranked among the coolest 25 percent on record (1895-2012) in all Midwest states except Michigan and Ohio. Though both September and October have been below normal, the 2012 year-to-date temperatures still rank as the warmest on record dating back to 1895 (Iowa, Minnesota, Missouri, and Wisconsin) or the second warmest (Illinois, Indiana, Kentucky, Michigan, and Ohio) for every state in the region.

    October precipitation varied widely with amounts less than a half inch (13 mm) in western parts of Minnesota and Missouri and totals exceeding 10 inches (254 mm) along the southern shore of Lake Erie. Totals were more than twice normal for October in most of Ohio, far eastern Kentucky, the thumb of Michigan, extreme northeast Minnesota, and a swath from southeast Minnesota to Upper Michigan. Snowfall in the Midwest was limited to the upper Midwest with totals of 3 to 5 inches (8 to 13 cm) in parts of northern Minnesota and Upper Michigan. Snow also fell in parts of Ohio and Kentucky as the remnants of Hurricane Sandy brought precipitation from the northeast seaboard all the way to the eastern reaches of the Midwest at the end of the month.

    Drought conditions improved slightly during October. Areas in drought dropped from about 70 percent to 56 percent while areas in extreme drought fell from 16 percent to 11 percent of the Midwest. Cooler temperatures have helped to lower evapotranspiration in the region allowing for more of the precipitation to help recharge soil moisture. Harvest continued ahead of normal across the region. All nine states were ahead of normal for corn harvest while soybean harvest was either near normal or slightly ahead of normal. According to the US Army Corps of Engineers, monthly lake wide mean levels on Lake Michigan-Huron and Lake Superior were near record lows during the month of October. By the end of October, the mean lake wide level of Lake Michigan-Huron was 576.6 feet (175.748 m), which is within 1.5 inches (38 mm) of the record October low set back in 1964 and 1965 and only about 7 inches (178 mm) above the all-time record low lake level of 576 feet (175.565 m) in March 1964. By the end of October, Lake Superior was 15 inches (381 mm) below the long-term October average.

    As noted by the Southeast Regional Climate Center, for the third straight month, mean temperatures were near normal across much of the Southeast region. The warmest weather occurred during the first week and towards the end of the month in advance of Hurricane Sandy, with temperatures exceeding 80 degrees F (26.7 degrees C) as far north as northern Virginia. The coldest weather of the month occurred following the passage of a cold front on the 8th and in the wake of Hurricane Sandy over the final four days of the month. A month after tying its warmest September on record, San Juan, PR recorded its fourth warmest October in a record extending back to 1898.

    Precipitation in October was below average across most of the Southeast. The driest locations were found across central and southern parts of Alabama, Georgia, and South Carolina, where monthly totals were less than 25 percent of normal, while the wettest locations were found across eastern sections of North Carolina and Virginia, where monthly totals exceeded 200 percent of normal in places. Precipitation in October was variable across Puerto Rico, with above normal precipitation along the northern half of the island and below normal precipitation along the southern half. Precipitation was generally above normal across the U.S. Virgin Islands, with a large portion tied to the passage of Hurricane Rafael on the 15th of the month.

    There were relatively few changes to the USDM across the Southeast in October. Abnormally dry conditions (D0) expanded across southeastern Georgia, central South Carolina, and south-central North Carolina. There was a slight contraction of moderate (D2) to exceptional (D4) drought across central Georgia, while Hurricane Sandy helped eliminate drought conditions across eastern and northern sections of Virginia. By the end of the month, approximately 40 percent of the Southeast was classified in drought. The overall dry pattern in October aided in the harvesting of row crops and fall vegetables as well as the planting of winter crops. Pastures were also reported to be in good condition due to the cooler temperatures, though newly planted pastures, particularly fescue and cool season forage, could benefit from some additional rainfall. The continued dry pattern across central Georgia forced some farmers to ship in water for their livestock to offset dropping farm pond levels. Livestock and crop conditions also declined across much of South Carolina due to the lack of rainfall. High winds from Sandy contributed to some cotton damage across eastern North Carolina and delayed the harvesting of several row crops. However, the rain from Sandy provided some much needed moisture for newly planted winter wheat. Several vegetable and tobacco growers in North Carolina reported above average yields for the year, while growers in Virginia reported that peanut and soybean yields have been above average.

    As explained by the Northeast Regional Climate Center, for the fourth month in a row, the Northeast was warmer than normal. While October started off dry, Hurricane/Superstorm Sandy brought record rainfall to parts of the Northeast. With a monthly total of 5.49 inches (139.45 mm), October was 143 percent of normal. Delaware received 8.89 inches (225.81 mm) of rain making it the wettest October since 1895. Maryland had its third wettest October with 4.21 inches (106.93 mm) of rain. Sandy also brought snow to parts of the Northeast. In fact it was the snowiest October on record (since 1948) for Charlestown, WV, with 10.1 inches (256.54 mm). Despite receiving rain from Sandy, Connecticut remained slightly drier than normal at 89 percent. While drought conditions improved across most of the Northeast, upstate New York was still experiencing abnormal dryness (D0) according to the USDM for October 30, 2012.

    As summarized by the Western Regional Climate Center, storms began marching across the Pacific Northwest mid-month, providing the first relief from a summer dominated by below normal precipitation and developing drought. Dry conditions persisted throughout the Southwest with the exception of southern Nevada, where a slow moving low-pressure system generated heavy precipitation and thunderstorms. After receiving no measurable precipitation for 84 days (July 21-Oct 12), Wenatchee, Washington recorded 1.56 in (39.6 mm) this month, 354% of normal and Wenatchee's 3rd wettest October on record. Missoula, Montana logged 1.82 in (46.2 mm) total precipitation and 4 in (10.2 cm) snow, making for the 6th wettest and 7th snowiest October in a record that began in 1893. Despite high precipitation totals this month, 60 percent of Montana remained in moderate to extreme drought. Las Vegas, Nevada saw its 9th wettest October in a record beginning in 1888 with a total of 0.73 in (18.5 mm). In just 3 months, August 1-October 31, 2012, Las Vegas received 4.19 in (106.4 mm) of precipitation, equal to the location's 30-year normal for annual precipitation. In contrast, the first 6 months of 2012 saw only 0.25 in (6.35 mm) in Las Vegas, the 6th driest January-June period on record. The same storm system that brought precipitation to the Las Vegas area also provided rainfall to Colorado's Front Range, helping to alleviate the persistent drought in this region. A cold front passed through the Front Range late in the month, bringing over 5 in (12.7 cm) of snowfall to Denver, bringing the city's total to 1.22 in (31.0 mm) of precipitation for October, 119 percent of normal. Wyoming also received some drought relief this month from the aforementioned storm systems. Normal to slightly above normal precipitation fell in the western and southeastern portions of the state, though at month's end, 97.8 percent of Wyoming remained at some level of drought. In the Southwest, Albuquerque, New Mexico recorded only trace precipitation this month, tying the 2nd driest October since official records began in 1933.

    In addition to dry conditions, above normal temperatures dominated the Southwest. Phoenix, Arizona recorded its 8th warmest October at 78.8 F (26.0 C), and Albuquerque, New Mexico noted its 10th warmest at 60.8 F (16 C). Records at Phoenix date back to 1895 and at Albuquerque to 1892. On October 6th, Ely, in northeastern Nevada, saw its second latest autumn freeze in an 89-year record, behind October 13, 1963. On the heels of its warmest August and September on record, Reno, Nevada posted an average October temperature of 58 F (14.4 C), the 5th warmest in a record beginning in 1888.

    Much further north, most of interior and southeast Alaska saw near or below normal temperatures this month. In contrast, the North Slope recorded average monthly temperatures 8-10 F (4-5 C) above normal. Barrow posted an October average of 27.5 F (-2.5 C), 10.3 F (5.7 C) above normal and the warmest since records began in 1949. This warmth is likely associated with the smallest measured summer minimum of polar ice extent, well below the former 2007 record. Out in the Pacific, Lihue, Hawaii set an all-time October high temperature record of 91 F (32.8 C) on October 9th. Lihue also recorded its driest October in a record that began in 1950, receiving only 0.39 in (9.9 mm) of rainfall, 9 percent of normal. Hilo, Hawaii also had a dry October at a total of 2.91 in (73.9 mm), its 3rd driest on record. All reporting stations in Hawaii received 75 percent or less of their normal October rainfall, further exacerbating the persistent drought conditions on the lee sides of the Islands.

    Upper Colorado River Basin: As reported by the Colorado Climate Center, the November 6th NIDIS (National Integrated Drought Information System) assessment for the Upper Colorado River Basin (UCRB) indicated that, for the month of October, most of the UCRB received below average precipitation. Southwest Colorado saw between 10 percent and 50 percent of average precipitation for the month. Some isolated areas in the northern CO mountains received near average precipitation. Northern Utah and western Wyoming received near to above average precipitation for the month (with some areas seeing over 200 percent of average moisture). East of the UCRB, northeast CO received near average precipitation for October while southeast CO and the San Luis Valley received below average precipitation. About half of the SNOTEL sites around the basin have started accumulating snowpack since the beginning of the water year. Very little to no snow has begun accumulating in the southern portion of the basin. Many of the northern sites have accumulated snow in the near normal range, while a few sites in central CO are showing below normal snowpack for this time of year.

    As of November 4th, about 26 percent of the USGS streamgages in the UCRB recorded normal (25th - 75th percentile) to above normal 7-day average streamflows. About 35 percent of the gages in the basin are recording much below normal or low (i.e. lowest on record) streamflows, and only one gage recorded above normal flows. Much below normal flows are found scattered throughout the basin. It is important to note that with baseflows dominating during this time of year, small changes in flows can lead to large percentile changes. The VIC soil moisture model shows extremely dry soils through most of WY, with soil dryness below the 20th percentile in northeast UT and northwest CO. Deteriorating soil moisture conditions are showing up over southwest CO. Dry soils also show up in southeast CO with near normal soil moisture in north-central CO and in the San Luis Valley in southern CO. For the month of October, all the major reservoirs in the UCRB saw a decrease in storage volumes, which is normal for this time of year. Lake Granby, Navajo, Dillon, and McPhee reservoirs saw larger decreases than normal while Lake Powell and Flaming Gorge saw smaller decreases than what is normal for this time of year.

    Pacific Islands: According to reports from National Weather Service offices, the Pacific ENSO Applications Climate Center (PEAC), and partners, conditions varied across the Pacific Islands.

    As noted by the National Weather Service office in Honolulu, instead of a seasonal increase in rainfall, October brought record low precipitation totals at several locations across the state. Most of the records broken were on Kauai and Oahu which resulted in a degradation of existing drought conditions. On Kauai...existing severe drought...or D2 category conditions in the USDM map...worsened to extreme drought...or the D3 category...in the southeastern portion of the island. For Oahu...moderate drought...or D1 conditions...worsened to severe drought levels on the leeward areas of the Waianae range. The rest of the state remains largely unchanged in terms of drought coverage. Extreme drought is entrenched over the southwest slopes of Lanai...western Molokai and southwest Maui from Kihei to Makena. Big Island extreme drought coverage includes most of the south Kohala district...the Pohakuloa region of the Hamakua district...the north-facing slopes of Hualalai in the north Kona district and the lower elevations of southwest Kau. Severe drought conditions in Maui county cover central and northeastern Lanai...the lower leeward slopes of the west Maui mountains...and the western slopes of Haleakala from Haiku to Kaupo. On the Big Island...the main area of severe drought is in the Humuula Saddle.

    Some drought impacts impacts in Hawaii include the following:

    KAUAI.
    EARLIER REPORTS INDICATED POOR PASTURE CONDITIONS IN THE AREA FROM
    KALAHEO TO HANAPEPE.  OTHER AREAS WITH POOR PASTURE CONDITIONS
    INCLUDE THE REGION FROM KOLOA TO MAHAULEPU...AND FROM KEALIA TO
    KALEPA.  THE WATER LEVEL IN THE ALEXANDER RESERVOIR IN SOUTH KAUAI
    HAS DROPPED SO LOW THAT IRRIGATION WATER SERVICE HAS BEEN
    SUSPENDED.  CATTLE HAVE BEEN REMOVED FROM THE MAHAULEPU AREA DUE TO
    POOR PASTURE CONDITIONS.
    
    OAHU.
    PASTURES AND GENERAL VEGETATION REMAIN IN POOR CONDITION OVER THE
    LEEWARD WAIANAE RANGE.  WEST OAHU RANCHERS HAVE DESTOCKED PASTURES
    DUE TO POOR GRAZING CONDITIONS.
    
    DESPITE THE RECORD DRY CONDITIONS...THE WATER SUPPLY IN THE
    WAIMANALO RESERVOIR REMAINS ABOVE PRE-DROUGHT LEVELS.  A VOLUNTARY
    10 PERCENT REDUCTION IN WATER USE REMAINS IN PLACE AS A PRECAUTION.
    
    MOLOKAI.
    NO SIGNIFICANT CHANGES SINCE THE OCTOBER 4 UPDATE.   PASTURES AND
    GENERAL VEGETATION CONDITIONS REMAIN VERY POOR WEST OF KAUNAKAKAI.
    
    THE WATER LEVEL IN THE KUALAPUU RESERVOIR REMAINS VERY LOW.
    THUS...THE STATE OF HAWAII DEPARTMENT OF AGRICULTURE HAS CONTINUED A
    MANDATORY 30 PERCENT REDUCTION IN IRRIGATION WATER CONSUMPTION.
    
    LANAI.
    NO SIGNIFICANT CHANGES SINCE THE OCTOBER 4 UPDATE.  AN EARLIER
    REPORT FROM LANAI INDICATED THAT THE MIDDLE AND LOWER ELEVATIONS OF
    THE ISLAND...ESPECIALLY ALONG THE NORTH-...EAST- AND SOUTH-FACING
    SLOPES...REMAIN VERY DRY AND THAT PLANTS AND ANIMALS IN THESE AREAS
    HAVE BEEN STRUGGLING TO SURVIVE.  EVEN DROUGHT-RESISTANT PLANTS AND
    TREES SUCH AS KIAWE WERE STRUGGLING UNDER THE DRY CONDITIONS.
    MOUFLON SHEEP...AXIS DEER AND GAME BIRD POPULATIONS HAVE BEEN
    REDUCED.
    
    MAUI.
    A LOW WATER SUPPLY HAS REDUCED PRODUCTION AT THE OLINDA WATER
    TREATMENT FACILITY IN UPCOUNTRY MAUI.  PASTURES AND GENERAL
    VEGETATION CONDITIONS REMAIN VERY POOR IN SOUTHWEST
    MAUI...ESPECIALLY FROM KAONOULU TO KAMAOLE.  PASTURES IN THIS AREA
    AND NEAR KAUPO WERE DESTOCKED SEVERAL MONTHS AGO DUE TO LACK OF
    SUFFICIENT FORAGE.  THE MAUI COUNTY DEPARTMENT OF WATER SUPPLY HAS
    CONTINUED THE ONGOING CALL FOR A 5 PERCENT REDUCTION IN WATER USE
    FOR UPCOUNTRY RESIDENTS.  THE REQUEST FOR A 10 PERCENT REDUCTION IN
    WATER USE BY CENTRAL AND SOUTH MAUI ALSO REMAINS IN EFFECT.
    
    BIG ISLAND.
    NO SIGNIFICANT CHANGES SINCE THE OCTOBER 4 UPDATE.  THE RECENT BELOW
    AVERAGE RAINFALL HAS SO FAR NOT PRODUCED SIGNIFICANT IMPACTS OVER
    THE WINDWARD SECTIONS OF THE ISLAND THOUGH THIS WILL CHANGE IF
    RAINFALL FAILS TO INCREASE SOON.  EARLIER REPORTS FROM THE
    KAU...NORTH KONA...SOUTH KONA AND SOUTH KOHALA DISTRICTS INDICATED
    SIGNIFICANT DROUGHT IMPACTS TO THE RANCHING, ORNAMENTAL PLANT, FRUIT
    ORCHARD, AND BEE INDUSTRIES.
    

    SPI values for seven time periods for Hawaiian Island stations, computed by the Honolulu NWS office.
    SPI values for seven time periods for Hawaiian Island stations

    On other Pacific Islands (maps — Micronesia, Marshall Islands, basinwide), October was drier than normal for Guam, Koror, Kwajalein, Lukonor, and Pohnpei, and much drier than normal for Majuro and Pago Pago. October rainfall amounts at Majuro and Pago Pago were well below six inches. Total rainfall for the last 12 months (November 2011-October 2012) was near to above normal for all stations except Majuro.


    X
    • Percent of Normal Precip
    • Precipitation
    • Normals
    Pacific Island Percent of 1981-2010 Normal Median Precipitation
    Station NameNov
    2011
    Dec
    2011
    Jan
    2012
    Feb
    2012
    Mar
    2012
    Apr
    2012
    May
    2012
    Jun
    2012
    Jul
    2012
    Aug
    2012
    Sep
    2012
    Oct
    2012
    Nov 2011-
    Oct 2012
    Chuuk136%125%57%181%107%40%173%131%141%169%86%128%117%
    Guam NAS83%103%162%94%215%121%224%107%66%179%126%92%103%
    Kapingamarangi81%124%109%71%121%102%143%179%146%192%147%138%115%
    Koror62%97%36%126%121%120%122%95%88%102%111%78%87%
    Kosrae95%174%65%185%60%84%86%99%124%144%109%113%92%
    Kwajalein130%84%134%114%84%68%161%117%120%95%57%73%97%
    Lukonor154%251%86%124%135%76%106%125%82%73%148%74%103%
    Majuro119%91%107%65%194%97%59%81%68%87%67%46%85%
    Pago Pago157%75%61%98%131%90%126%115%105%59%195%54%90%
    Pohnpei123%110%82%138%98%45%115%100%92%96%90%82%93%
    Saipan57%110%77%183%35%33%166%118%77%135%101%172%110%
    Yap112%116%33%117%185%89%142%99%84%128%187%140%115%
    Pacific Island Precipitation (Inches)
    Station NameNov
    2011
    Dec
    2011
    Jan
    2012
    Feb
    2012
    Mar
    2012
    Apr
    2012
    May
    2012
    Jun
    2012
    Jul
    2012
    Aug
    2012
    Sep
    2012
    Oct
    2012
    Nov 2011-
    Oct 2012
    Chuuk14.4414.015.7413.138.875.0219.5615.2716.9221.7810.0414.68159.46
    Guam NAS6.145.246.502.854.453.057.636.636.7426.4215.9810.56102.19
    Kapingamarangi7.5412.199.946.6113.8213.9117.2424.6820.6515.5714.5611.32168.03
    Koror7.0410.793.6510.819.038.7914.4916.5416.3613.7213.019.23133.46
    Kosrae13.0728.1110.8923.939.5914.7015.3514.5618.5520.4615.5212.33197.06
    Kwajalein14.685.594.223.011.973.5810.828.0811.839.236.178.1887.36
    Lukonor14.0228.347.2211.0612.518.6012.3514.5313.0810.2615.028.39155.38
    Majuro15.9710.378.274.4612.759.145.968.897.5410.157.475.84106.81
    Pago Pago15.919.698.1411.7614.008.4112.156.135.843.1912.734.99112.94
    Pohnpei18.2117.6110.7513.1712.928.3122.9814.8614.2113.6211.2712.59170.5
    Saipan3.224.231.964.750.660.883.964.266.8617.7310.2418.3177.06
    Yap9.929.912.116.098.435.0011.1411.9512.7418.9225.1917.08138.48
    Pacific Island 1981-2010 Normal Median Precipitation (Inches)
    Station NameNov
    2011
    Dec
    2011
    Jan
    2012
    Feb
    2012
    Mar
    2012
    Apr
    2012
    May
    2012
    Jun
    2012
    Jul
    2012
    Aug
    2012
    Sep
    2012
    Oct
    2012
    Nov 2011-
    Oct 2012
    Chuuk10.6111.2510.107.258.3212.4711.3011.6611.9812.8611.7111.51136.77
    Guam NAS7.385.114.013.032.072.533.406.1810.1414.7412.6611.4499.09
    Kapingamarangi9.279.849.159.2711.4313.6412.0813.7814.158.139.938.19145.85
    Koror11.3911.1610.188.567.447.3211.8317.4818.5313.5011.7711.84152.90
    Kosrae13.8316.1116.6712.9316.0617.5117.7514.6414.9114.2214.2210.94213.87
    Kwajalein11.286.663.162.642.355.266.726.939.879.7410.7411.1890.41
    Lukonor9.0811.278.418.939.2611.3111.6911.6515.9314.0410.1511.32151.36
    Majuro13.4411.397.746.886.589.4210.1111.0111.1711.6911.1712.73125.25
    Pago Pago10.1412.8413.3412.0010.689.399.665.335.555.386.539.26125.57
    Pohnpei14.8316.0813.189.5513.1718.4119.9614.8115.4314.2612.5515.27182.36
    Saipan5.613.852.532.591.892.632.383.628.9113.1310.0910.6270.25
    Yap8.838.516.395.194.565.637.8512.0415.0814.8213.5012.18120.31

    Percent of normal precipitation for current month for U.S. Affiliated Pacific Islant stations

    SPI values for seven time periods for Pacific Islands, computed by the Honolulu NWS office.
    SPI values for seven time periods for Pacific Islands

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    State/Regional/National Moisture Status
    A detailed review of drought and moisture conditions is available for all contiguous U.S. states, the nine standard regions, and the nation (contiguous U.S.):

    States
    alabama arizona arkansas california colorado connecticut
    delaware florida georgia idaho illinois indiana
    iowa kansas kentucky louisiana maine maryland
    massachusetts michigan minnesota mississippi missouri montana
    nebraska nevada new hampshire new jersey new mexico new york
    north carolina north dakota ohio oklahoma oregon pennsylvania
    rhode island south carolina south dakota tennessee texas utah
    vermont virginia washington west virginia wisconsin wyoming

    Regional
    northeast u. s. east north central u. s. central u. s.
    southeast u. s. west north central u. s. south u. s.
    southwest u. s. northwest u. s. west u. s.

    National
    Contiguous United States

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    Drought Indicators
    The following indicators illustrate the drought conditions this month:

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    Contacts & Questions
    For additional, or more localized, drought information, please visit:

    Global Snow & Ice

    NH Snow Cover Extent

    Data were provided by the Global Snow Laboratory, Rutgers University. Period of record is 1967-2012 (45 years, no data availble for October 1969).

    October marks the beginning of the cold season for the Northern Hemisphere and storms begin bringing snow to the higher latitudes and elevations. During October 2012, the Northern Hemisphere snow cover extent was 1.9 million square km (734,000 square miles) above the long-term average of 17.96 million square km (6.9 million square miles). This monthly value ranks as the eighth largest October snow cover extent in the 45-year period of record.

    Across North America, snow cover extent for October 2012 was above average. Canada had much above average snow cover during the month, while the contiguous U.S. experienced below-average snow cover. The North American snow cover extent was 696,000 square km (269,000 square miles) above the long-term average of 8.1 million square km (3.1 million square miles). For the continent, above-average snow cover was observed across the Canadian Rockies and Prairies, while the U.S. Rockies and much of Alaska experienced below-average snow cover. For more information on the U.S. October 2012 snow events, please visit the U.S. October Snow/Ice Summary page.

    Eurasian snow cover extent was also above average for October 2012, with a spatial extent of 11.1 million square km (4.3 million square miles), 1.2 million square km (463,000 square miles) above average. This was the 11th largest October snow cover extent on record for the continent. Above-average snow cover was observed for much of Russia and the Tibetan Plateau, while below-average snow cover was observed for the Himalayas.

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    Sea Ice Extent

    According to the National Snow and Ice Data Center (NSIDC), the Northern Hemisphere sea ice extent — which is measured from passive microwave instruments onboard NOAA satellites — averaged for October 2012 was 7.00 million square km (2.70 million square miles). The monthly extent was 24.61 percent below average and ranked as the second smallest October Northern Hemisphere sea ice extent in the satellite record. The October 2012 Arctic sea ice extent was 230,000 square km (88,800 square miles) larger than the smallest October extent on record that occurred in 2007. Arctic sea ice rapidly expanded during October, after reaching an annual minimum in September, doubling in size between October 1st and 31st. October average Arctic sea ice has declined at a rate of 7.1 percent per decade.

    According to analysis from the NSIDC, sea ice rapidly expanded into the East Siberian, Chukchi, and Laptev seas which were nearly completely frozen by the end of October. Conversely, the Kara, southern Beaufort, and Barents seas were much slower to freeze. The fast pace freezing of some regions of the Arctic was not enough to compensate for the slow freezing in other regions and make up the large ice extent deficits experienced during the late summer of 2012. At the end of October, Arctic sea ice extent continued to be much below average and near record-low levels.

    The October 2012 Southern Hemisphere sea ice extent was 18.88 million square km (7.3 million square miles), 3.36 percent above average and the third largest October sea ice extent in the 1979-2012 period of record. Antarctic sea ice extent during October has increased at an average rate of 0.9 percent per decade, with substantial interannual variability.

    For further information on the Northern and Southern Hemisphere snow and ice conditions, please visit the NSIDC News page.

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    Upper Air


    Note: University of Alabama in Huntsville scientists advise that the AMSU channel 5 on the AQUA satellite, which has heretofore been the anchor-source of data in the construction of low- and mid-tropospheric temperatures (LT and MT) since 2002, was experiencing gradually increasing noise since 2009. However, a relatively rapid increase in noise in the recent few months to September 2012 generated clearly erroneous values. Therefore, beginning September 2012, these datasets (LT and MT) switched from AQUA to the AMSU channel 5 on NOAA-15 and NOAA-18, replacing AQUA data after 2009 in version 5.5.

    Troposphere

    Lower Troposphere

    October Lower Troposphere
    October Anomaly Rank
    (out of 34 years)
    Record Years Decadal Trend
    °C °F Year °C °F °C °F
    UAH +0.34 +0.61 Coolest 33rd 1985 -0.41 -0.74 +0.17 +0.31
    Warmest 2nd 2005 +0.36 +0.65
    RSS +0.20 +0.36 Coolest 27th 1985 -0.38 -0.68 +0.14 +0.25
    Warmest 7th 1998 +0.37 +0.67
    Ties: 2009
    Year-to-Date Lower Troposphere
    January–
    October
    Anomaly Rank
    (out of 34 years)
    Record Years Decadal Trend
    °C °F Year °C °F °C °F
    UAH +0.15 +0.27 Coolest 26th 1985, 1984 -0.32 -0.58 +0.14 +0.25
    Warmest 9th 1998 +0.48 +0.86
    RSS +0.10 +0.18 Coolest 24th 1985 -0.38 -0.68 +0.14 +0.24
    Warmest 11th 1998 +0.51 +0.92

    Mid-troposphere

    October Mid-troposphere
    October Anomaly Rank
    (out of 34 years)
    Record Years Decadal Trend
    °C °F Year °C °F °C °F
    UAH +0.21 +0.38 Coolest 30th 1985 -0.34 -0.61 +0.08 +0.14
    Warmest 4th 1998 +0.31 +0.56
    Ties: 2010
    RSS +0.24 +0.43 Coolest 32nd 1985 -0.41 -0.74 +0.10 +0.18
    Warmest 3rd 1998 +0.33 +0.59
    UW-UAH +0.25 +0.45 Coolest 29th 1985 -0.39 -0.70 +0.15 +0.27
    Warmest 6th 1998 +0.43 +0.77
    UW-RSS +0.27 +0.49 Coolest 30th 1985 -0.44 -0.79 +0.15 +0.28
    Warmest 5th 1998 +0.43 +0.77
    Year-to-Date Mid-troposphere
    January–
    October
    Anomaly Rank
    (out of 34 years*)
    Record Years Decadal Trend
    °C °F Year °C °F °C °F
    UAH 0.00 0.00 Coolest 17th 1993, 1989, 1984 -0.24 -0.43 +0.05 +0.08
    Warmest 17th 1998 +0.49 +0.88
    Ties: 1995
    RSS +0.05 +0.09 Coolest 20th 1985 -0.29 -0.52 +0.08 +0.15
    Warmest 14th 1998 +0.50 +0.90
    Ties: 1988
    UW-UAH +0.05 +0.09 Coolest 19th 1984 -0.32 -0.58 +0.11 +0.19
    Warmest 12th 1998 +0.59 +1.06
    Ties: 2011, 1995, 1988, 1983
    UW-RSS +0.11 +0.20 Coolest 24th 1985, 1984 -0.32 -0.58 +0.14 +0.25
    Warmest 10th 1998 +0.58 +1.04
    Ties: 2009
    RATPAC* +0.14 +0.25 Coolest 46th 1965 -0.82 -1.48 +0.15 +0.27
    Warmest 10th 2010 +0.54 +0.97

    *RATPAC rank is based on 55 years of data

    Stratosphere

    October Stratosphere
    October Anomaly Rank
    (out of 34 years)
    Record Years Decadal Trend
    °C °F Year °C °F °C °F
    UAH -0.38 -0.68 Coolest 10th 2000 -0.65 -1.17 -0.44 -0.78
    Warmest 25th 1991 +1.59 +2.86
    RSS -0.35 -0.63 Coolest 9th 2000 -0.55 -0.99 -0.34 -0.60
    Warmest 26th 1991 +1.58 +2.84
    Year-to-Date Stratosphere
    January–
    October
    Anomaly Rank
    (out of 34 years)
    Record Years Decadal Trend
    °C °F Year °C °F °C °F
    UAH -0.43 -0.77 Coolest 3rd 2008, 1996 -0.47 -0.85 -0.36 -0.65
    Warmest 32nd 1983 +1.01 +1.82
    RSS -0.42 -0.76 Coolest 1st 2012 -0.42 -0.76 -0.29 -0.52
    Warmest 34th 1992 +0.98 +1.76

    Background Information

    Temperatures above the Earth's surface are measured within the lower troposphere, middle troposphere, and stratosphere using in-situ balloon-borne instruments (radiosondes) and polar-orbiting satellites (NOAA's TIROS-N). The radiosonde and satellite records have been adjusted to remove time-dependent biases (artificialities caused by changes in radiosonde instruments and measurement practices as well as changes in satellite instruments and orbital features through time). Global averages from radiosonde data are available from 1958 to present, while satellite measurements date back to 1979.

    The mid-troposphere temperatures are centered in the in the atmospheric layer approximately 3–10 km [2–6 miles] above the Earth's surface, which also includes a portion of the lower stratosphere. (The Microwave Sounding Unit [MSU] channel used to measure mid-tropospheric temperatures receives about 25 percent of its signal above 10 km [6 miles].) Because the stratosphere has cooled due to increasing greenhouse gases in the troposphere and losses of ozone in the stratosphere, the stratospheric contribution to the tropospheric average, as measured from satellites, creates an artificial component of cooling to the mid-troposphere temperatures. The University of Washington (UW) versions of the UAH and RSS analyses attempt to remove the stratospheric influence from the mid-troposphere measurements, and as a result the UW versions tend to have a larger warming trend than either the UAH or RSS versions. For additional information, please see NCDC's Microwave Sounding Unit page.

    The radiosonde data used in this global analysis were developed using the Lanzante, Klein, Seidel (2003) ("LKS") bias-adjusted dataset and the First Difference Method (Free et al. 2004) (RATPAC). Additional details are available. Satellite data have been adjusted by the Global Hydrology and Climate Center at the University of Alabama in Huntsville (UAH). An independent analysis is also performed by Remote Sensing Systems (RSS) and a third analysis has been performed by Dr. Qiang Fu of the University of Washington (UW) (Fu et al. 2004)** to remove the influence of the stratosphere on the mid-troposphere value. Global averages from radiosonde data are available from 1958 to present, while satellite measurements began in 1979.

    References

    Wildfires

    Updated: 7 November 2012


    Overview

    Large wildfires abated in the Pacific Northwest, and new fire incident locations transitioned from the northern Rockies into the central Rockies and High Plains during October. At the end of the month, a concentration of wildfires flared along the Cumberland Mountains in eastern Kentucky, northeastern Tennessee, and western Virginia (west side of the Appalachian Mountains).

    The monthly average fire size reached 56.5 acres per fire, which was the 6th highest for any October in the 2000-2012 record and slightly below the 10-year average of 66.3 acres per fire. However, the year-to-date fire size of 173.8 acres was the most since 2000 for any January through October period, and nearly twice the 10-year average (based on 2001-2010).

    The October acreage burned represented about one-fifth the amount burned in September. The monthly total of 0.2 million acres burned by wildfires ranked at the median value (7th highest and 7th lowest) for any October since 2000, yet the year-to-date total acreage burned of 9.0 million acres was the 2nd highest since 2000. Notably, the year-to-date acreage burned in 2012 represents about 1.5 times the 10-year average (based on 2001-2010).

    The number of October fires remained approximately equal to September's number. The monthly total number of 3,553 fires was the median value (7th least and 7th most) for October in the thirteen-year record. Yet, the year-to-date total of 51,811 fires was the least since 2000 for any January through October period and represented only three-quarters of the 10-year average number. Thus, despite the fire size in October being only one-fifth in size for roughly the same number of fires compared with the previous month, the year-to-date tendency of fewer fires (least) — but larger in size (most) — was preserved.

    1-Month Wildfire Statistics*
    October Totals Rank
    (out of 13 years)
    Record 2000-2010
    Average
    Value Year
    Acres Burned 200,860 7ᵗʰ Most 507,724 2011 211,434
    7ᵗʰ Least
    Number of Fires 3,553 7ᵗʰ Most 7,651 2000 4,271
    7ᵗʰ Least
    Acres Burned per Fire 56.5 6ᵗʰ Most 158.9 2004 62.6
    8ᵗʰ Least
    Year-to-Date Wildfire Statistics*
    January–October Totals Rank
    (out of 13 years)
    Record 2000-2010
    Average
    Value Year
    Acres Burned 9,003,581 2ⁿᵈ Most 9,400,909 2006 6,242,529
    12ᵗʰ Least
    Number of Fires 51,811 13ᵗʰ Most 87,809 2000 70,251
    Least on Record
    Acres Burned per Fire 173.8 Most on Record 173.8 2012 88.9
    13ᵗʰ Least

    *Data Source: The National Interagency Fire Center (NIFC)

    Discussion

    Throughout October, extreme drought (D3) and higher was concentrated over the central U.S., stretching east of the Rockies to the Mississippi Valley, according to the 30 October 2012 U.S. Drought Monitor. The significant moisture deficits (> 600 units) indicated by the Keetch-Byram Drought Index (KBDI) closely aligned with the extreme drought conditions across much of western and northern Nevada and exceptional drought (D4) in central South Dakota and Nebraska. These dry areas were the sites of wildfires during the month, with fire incidents occurring along the Nevada and Idaho border in early October, and incidents flaring in South Dakota and Nebraska at mid-month. For the January to October 2012 period, both Nebraska and Wyoming experienced their driest period on record since 1895, resulting in these states having the worst rangeland and pasture conditions within the United States. Severe drought (D2) expanded slightly in Arizona and New Mexico during late October, which coincided with an increase of wildfire occurrences across the Southwest. Please see the U.S. temperature and precipitation report for additional information.

    Significant Events


    Please note, this is a list of select fires that occurred during October. Additional fire information can be found through Inciweb.


    Idaho

    Low fuel moistures at all intervals (10-hour, 100-hour, and 1000-hour) and abnormally dry conditions through the first half of October, kept the wildfire danger elevated in central Idaho. The location of the Powell Selway-Bitterroot Wilderness Complex closely aligned with high KBDI moisture deficit values (> 700 units). The wildfire (comprised of three main and numerous small fires) consumed at least 67,000 acres of timber since being ignited by lightning in late July, including about 6,000 acres that burned during October in the Clearwater National Forest. The fire produced heavy smoke over northeastern Idaho and northwestern Montana, impacting air quality for residents. Rainfall of approximately 50 mm (2 inches) at mid-month aided in fire suppression efforts, which reached an estimated $4.8 million U.S. dollars. The Sheep Fire, a wildfire that originated during early September, consumed over 48,000 acres of brush, grass, and timber by mid-October, when rains helped impede the fire's spread. The blaze, which destroyed at least one commercial building at a mining camp in the fire's early stages, threatened logging operations and livestock in northwestern Idaho, according to media reports. The fire's estimated suppression costs topped $17 million U.S. dollars. Rain and snow toward the month's end doused the Wesley wildfire's flames. The fire burned 16,000 acres of subalpine fir in northwestern Idaho's steep terrain after being sparked by lightning in the previous month. Two firefighters received injuries while battling the blaze which threatened over 22 structures and a bridge. The fire's suppression efforts exceeded $14 million U.S. dollars.

    Minnesota

    Gusty winds fanned the Wannaska Complex, which consisted of at least eight wildfires in northwest Minnesota and burned over 30,000 acres during early October. Dryness and low humidity gave rise to extreme fire danger in the region, before rain and snow relieved the situation on October 4th. Fuels included timber, peat, grasses, swamps, and conifers. Peat is formed by decayed vegetation and contains trapped oxygen, allowing dry peat to smolder for long periods as it burns. Peat fires are difficult to extinguish, and limited the fire crews to a rate of about five acres per day in ending those incidents. Because the peat layer extended to 0.5 m (18 inches) in depth, the precipitation was not expected to fully snuff the peat fires, according to media reports. One of the larger fires, the County 27 wildfire, which burned over 4,700 acres of timber and grass in Kittson County, destroyed 11 homes, 24 other structures, and resulted in the evacuation of the town of Karlstad (over 750 residents). The largest incident, the North Minnie Fire near Red Lake charred nearly 25,000 acres of timber, grass, and peat in Beltrami County, resulting in the closure of area roads and trails near the town of Fourtown. One home and four outbuildings were destroyed in the town of Lancaster by the Richardville Border Fire as it burned about 1,000 acres of timber and grass in the nearby Canadian province of Manitoba.

    Kentucky

    In October, Kentucky braced for an active fire season based on the abundance of wildfire fuels coupled with dry conditions. Spring tornadoes left storm-damaged trees, summer brought little rain, and the autumn leaf drop increased the surface fuel layer throughout the Appalachian forests. Fourteen wildfires in 12 Kentucky counties were burning on October 26th. In Clay County, a wildfire grew to about 100 acres near the Sattler Branch community where firefighters applied water to the exterior of a home and prevented its loss to flames. In Estill County, a 50-acre fire produced haze for the town of Irvine. In Rowan County, a wildfire scorched about 75 acres in the steep terrain of the Daniel Boone National Forest to the east of Morehead State University. The fire threatened homes, barns, and power lines after jumping the containment line, while its thick smoke impacted visibility along the U.S. 60 highway. Meanwhile, a series of brush fires erupted along the borders of West Virginia and Ohio.

    Monthly Wildfire Conditions

    Wildfire information and environmental conditions are provided by the National Interagency Fire Center (NIFC) and the U.S. Forest Service (USFS) Wildland Fire Assessment System (WFAS).

    Dry fuels and above normal temperatures fostered wildfire conditions in central Idaho and Washington, where numerous September fires continued to burn in October. Isolated incidents sparked in northern and southern California, as parts of the state experienced extremely low fuel moistures (below 6 percent) at all intervals (10-hour, 100-hour, and 1000-hour) early in the month. The Flynn wildfire, which sparked in northern California on October 1st, injured one person, destroyed one home and nine outbuildings, while threatening 70 other structures in Mendocino County, according to media reports. The fire scorched nearly 200 acres of commercial timber before being contained on October 4th and caused significant smoke across the Ukiah Valley and Lake County.


    Low fuel moistures (below 10 percent at 100-hour interval) at mid-month aligned with wildfire incidents in central Arizona, northern Colorado, western Nebraska, and the southwestern corner of South Dakota. Arizona's Big Canyon wildfire was sparked by lightning on October 14th, forcing closure of trails in the Tonto National Forest. The fire scorched over 100 acres of chaparral and timber with grass understory near Payson, Arizona. In the southwestern corner of Colorado, the Vallecito wildfire ignited on October 12th, burned 600 acres in the San Juan National Forest during the month, and initially posed a threat to about 20 homes nearby. By early November the blaze grew by 400 acres, fueled by fallen leaves, dead Gambel oak brush, and dead ponderosa pine. In Colorado's Rocky Mountain National Park, the Fern Lake Fire consumed over 1,000 acres of beetle-killed lodgepole and ponderosa pines during October. An accumulation of thick duff existed in the Forest Canyon area where the last fire occurred in 1862, according to media reports. Despite a heavy, wet snowfall late in October of up to 100 mm (4 inches), the wildfire that ignited on October 9th continued smoldering at the month's end. The Crookston wildfire began in South Dakota on October 17th, but quickly crossed into Nebraska where the residents of Crookston were evacuated, and at least seven structures were severely damaged. Gusty winds spread the grass fire and forced a temporary closure along the U.S. 20 highway. Two additional wildfires in Nebraska burned about 4,000 acres around the same time.


    In the latter part of October, fuel moistures at the 100-hour and 1000-hour intervals lowered to below 10 percent across the southwestern states. Wildfire incidents in southern Colorado, northern New Mexico, and eastern Arizona were closely aligned with areas of extremely low 10-hour fuel moistures (below 5 percent). The Wetmore Fire ignited on October 23rd and destroyed 15 homes near Pueblo, Colorado. Strong winds fanned the wildfire, which consumed close to 2,000 acres of timber and grass, while forcing evacuation of nearly 400 residents. In southwestern Colorado, Roatcap Fire threatened around 100 homes and high voltage power lines near Dolores in Montezuma County on October 24th. The wildfire's flames charred over 400 acres of timber, piñon pine, and juniper. The Red Cross provided shelter and meals for residents of the 30 homes which were evacuated, according to media reports. In New Mexico's Carson National Forest, the Midnight wildfire sparked on October 23rd and burned over 360 acres of timber and grass east of Taos. Voluntary evacuations of two Valle Vidal campgrounds occurred as a precautionary measure. Light snow on October 26th, the onset of cooler temperatures, and higher humidity helped curb the wildfire. The Shorten wildfire remained active in southeastern Arizona, having scorched over 6,100 acres of juniper and ponderosa pine near San Carlos since September 25th. The Lookout wildfire near Santa Barbara in southern California threatened about 100 homes on October 17th, possibly sparked as a result of a downed power line. The fire burned over 40 acres of brush and forced brief evacuation of residents of Painted Cave.


    All Fire Related Maps


    Citing This Report

    NOAA National Climatic Data Center, State of the Climate for October 2012, published online November 2012, retrieved on December 21, 2014 from http://www.ncdc.noaa.gov/sotc/2012/10.