Entire Report - November 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:



November Extreme Weather/Climate Events

Supplemental November and January-November Information


  • Climate Highlights — November
  • The average temperature for the contiguous U.S. during November was 44.1°F, 2.1°F above the 20th century average, tying 2004 as the 20th warmest November on record.
  • November brought warmer-than-average conditions to the western half of the country. The largest temperature departures from average were centered near the Rockies where Arizona, Colorado, New Mexico, Utah, and Wyoming had November temperatures among their ten warmest.
  • The Eastern Seaboard, Ohio Valley, and Southeast were cooler than average during November. North Carolina tied its 10th coolest November on record, with a statewide-averaged temperature 3.5°F below average.
  • The November nationally-averaged precipitation total of 1.19 inches was 0.93 inch below the long-term average and the 8th driest November on record. A large area of the country experienced below-average precipitation in November. Drier-than-average conditions stretched from the Intermountain West, through the Plains, into the Midwest, and along the entire East Coast. Twenty-two states had monthly precipitation totals ranking among their ten driest.
  • According to the November 27th, 2012 U.S. Drought Monitor report, 62.7 percent of the contiguous U.S. was experiencing moderate-to-exceptional drought, larger than the 60.2 percent at the end of October. Drought conditions improved for parts of the Northern Rockies, which were wetter than average during November, while they worsened for parts of the Southwest, Southeast, and Mid-Atlantic.
  • Climate Highlights — Autumn (September-November)
  • The contiguous U.S. temperature of 54.7°F was the 21st warmest autumn, 1.1°F above average.
  • Autumn temperatures were above average across much of the western United States. Nevada had its warmest autumn on record, with a seasonal temperature 3.7°F above average. Arizona, California, Idaho, New Mexico, Utah, and Wyoming each had a top ten warm autumn.
  • The Ohio Valley and Southeast experienced below-average autumn temperatures. Kentucky autumn temperatures were the sixth coolest while Mississippi had its 10th coolest autumn.
  • The autumn precipitation total for the contiguous U.S. was 5.71 inches, 1.0 inch below average.
  • Autumn precipitation totals were drier than average for the central U.S. and parts of the Southeast. Minnesota, Nebraska, and South Dakota each had a top ten dry autumn. Wetter-than-average conditions were present for the Pacific Northwest, the Ohio Valley, and parts of the Northeast.
  • 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 above average during the September-November period. Extremes in warm daytime temperatures, warm nighttime temperatures, and the spatial extent of drought conditions contributed to the elevated USCEI value.
  • Climate Highlights — Year-to-Date (January-November)
  • The January-November period was the warmest first 11 months of any year on record for the contiguous United States. The national temperature of 57.1°F was 3.3°F above the 20th century average, and 1.0°F above the previous record warm January-November of 1934. During the 11-month period, 18 states were record warm and an additional 24 states were top ten warm.
  • It appears virtually certain that 2012 will surpass the current record (1998, 54.3°F) as the warmest year for the nation. December 2012 temperatures would need to be more than 1.0°F colder than the coldest December (1983) for 2012 to not break the record.
  • January-November 2012 was the 12th driest such period on record for the contiguous U.S., with a precipitation total 3.08 inches below the long-term average of 26.91 inches.
  • Drier-than-average conditions stretched across the central part of the country, from the Rocky Mountains to the East Coast. Colorado, Nebraska, and Wyoming each had their driest year-to-date on record and eight additional states had 11-month precipitation totals among their ten driest.
  • Wetter-than-average conditions were present for the Pacific Northwest, the central Gulf Coast, and New England. Washington State experienced its ninth wettest year-to-date.
  • The USCEI was more than twice the average value during January-November, and marked the 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.
  • Climate Highlights — 12-month period (December 2011-November 2012)
  • The December 2011-November 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 average. This 12-month temperature average was the sixth warmest of any 12-month period on record for the contiguous United States. The eight warmest 12-month periods have all ended during 2012.

Alaska Temperature and Precipitation:

  • Alaska had its 26th coolest November since records began in 1918, with a temperature 3.1°F (1.7°C) below the 1971–2000 average.
  • Alaska had its 29th coolest September-November since records began in 1918, with a temperature 1.1°F (0.6°C) below the 1971–2000 average.
  • Alaska had its 13th coolest January-November since records began in 1918, with a temperature 2.0°F (1.1°C) below the 1971–2000 average.
  • Alaska had its 28th driest November since records began in 1918, with an anomaly that was 19.8 percent below the 1971–2000 average.
  • Alaska had its 25th wettest September-November since records began in 1918, with an anomaly that was 11.6 percent above the 1971–2000 average.
  • Alaska had its 24th wettest January-November since records began in 1918, with an anomaly that was 13.1 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)
  • Despite a mid-month warm up, the Northeast was cooler than normal for November 2012. With an average temperature of 37.2 degrees F (2.9 degrees C), it was 2.5 degrees F (1.4 degrees C) cooler than normal and the coolest November since 1997. All states reported below average temperatures for the first time since October 2009. West Virginia and Maine were the coolest at 4.1 degrees F (2.3 degrees C) below average. It was West Virginia’s 16th and Maine’s 18th coolest November in 118 years. Departures for the rest of the states ranged from 4.0 degrees F (2.2 degress C) below normal in New Jersey to 0.9 degrees F (0.5 degrees C) below normal in Vermont. Autumn’s average temperature of 50.0 F (10.0 degrees C) was average for November in the Northeast. Five states reported cooler than average temperatures while the other seven were slightly warmer than average. West Virginia was the coolest at 1.6 degrees F (0.9 degrees C) below average making it their 19th coolest autumn on record. Of the warm states, Vermont was the warmest at 1.1 degrees F (0.6 degrees C) above average.
  • Even though it was a wet start to the month for several states, November 2012 went into the record books as the 2nd driest since 1895. With an average of 1.04 inches (26.42 mm), the region received only 27 percent of normal precipitation. The record driest November was 1917 when the Northeast received only 0.88 inches (22.35 mm) of precipitation. All states were drier than average. Departures ranged from 16 percent of normal in Connecticut, their 2nd driest November, to 37 percent of normal in New Jersey, their 11th driest. Of the remaining states, New Hampshire, Vermont and West Virginia had their 2nd driest November; Delaware, Maine, Maryland and New York had their 3rd driest; and in Pennsylvania, Rhode Island, and Massachusetts November ranked in the top 10 driest. The Northeast was slightly drier than average for autumn with 11.36 inches (288.54 mm) of precipitation (98 percent of normal). The region was split down the middle with half of the states drier and half the states wetter than normal. Connecticut took the title of driest state with only 78 percent of normal while Delaware led the wet states with 120 percent of normal. The latest US Drought Monitor, issued November 27, indicated abnormal dryness continued in upstate New York while a new area of abnormal dryness popped up near the Vermont-New Hampshire border and in central/southern West Virginia.
  • At the start of November, the Northeast was still dealing with the aftermath of Sandy. Damage to fuel terminals and power outages caused twelve northern counties of New Jersey, New York City, and Long Island to institute gas rationing. It was the first time since the energy crisis of the 1970s that New York City had implemented this system. The rationing lasted just over two weeks in New York City and 10 days in New Jersey. As per the Associated Press, the estimated cost of recovering and rebuilding from Sandy increased to $42 billion in New York and to $37 billion in New Jersey. A Nor’easter dropped snow on areas still trying to clean up from Sandy on the 7th and 8th. Some inland areas received over a foot of snow and more than twenty snowfall records were set, in some cases for the first time, at sites from Maryland up to Maine. For instance, JFK Airport, NY, reported 4.0 inches (101.6 mm) of snow on the 7th and 0.3 inches (7.6 mm) on the 8th. Snowfall had never been recorded on those dates. High winds, with gusts above 60 mph (26.8 m/s), downed already vulnerable trees and power lines. Around 115,000 new power outages (according to NBC News) were reported in places where many people had just gotten power back. According to the Department of Energy website, “All customers who are able to receive electricity and who lost power due to Sandy and the Nor’easter have had their electricity restored. As of December 3, in New Jersey there are less than 19,000 customers and in New York there are less than 17,000 customers who are unable to accept electric service.” A couple days later, a mid-month warm-up, with temperatures topping out from 65 degrees F (18.3 degrees C) to 75 degrees F (23.9 degrees C), broke high temperature records in several cities in the Northeast. Just after Thanksgiving, the lake-effect season kicked off in parts of New York. On the 25th, a band of snow off Lake Erie dropped up to 7.0 inches (177.8 mm) around Buffalo. The snow continued into the 26th off of Lake Ontario dropping up to 15.0 inches (381.0 mm) in parts of New York’s North Country. Holiday traffic was disrupted when the southbound side of Interstate 81 was closed and the northbound side was backed up for several hours in Oswego County on the 25th due to weather-related accidents.
  • For more information, please go to the Northeast Regional Climate Center Home Page.
  • Midwest Region: (Information provided by the Midwest Regional Climate Center)
  • November temperatures in the Midwest were moderate with departures ranging from 2 degrees F (1 C) along the Iowa-Minnesota border to as much as 5 degrees F (3 C) below normal in parts of eastern Kentucky. Two warm spells during the month, the first coming on the 10th to the 12th and the second on the 22nd and 23rd, were responsible for most of the 600 plus daily temperature records. Just dozens of record lows were recorded. Fall, September to November, temperatures ranged from near normal to below normal across the region. Kentucky ranked as the 6th coolest fall dating back to 1895 with temperatures 2.2 degrees F (1.2 C) below normal. The cooler November and fall temperatures have cooled the year-to-date temperatures slightly but all nine states remain among the five warmest January to November periods dating back 118 years.
  • November precipitation was below normal across the Midwest. Only small pockets of northern Minnesota and Upper Michigan reached normal for the month while all nine states had areas with less than 25 percent of normal. Most of the southeastern half of the region received less than half of their normal precipitation in November. Statewide totals in Ohio (4th), Indiana (4th), Kentucky (5th), and Michigan (7th) all ranked among the 10 driest Novembers since 1895. Fall precipitation totals ranged widely from southern Illinois and northern Ohio with over 150 percent of normal to most of Minnesota with less than 50 percent of normal for the three-month period. Year-to-date statewide precipitation totals ranged from 70 percent to 95 percent of normal. Iowa (8th) and Missouri (9th) ranked among the top 10 driest January to November periods since 1895.
  • Drought remained a serious issue in the western half of the Midwest. Moderate drought extended across most of the western half of the region with areas of extreme drought in Minnesota and Iowa at the end of the month. A little over half (55 percent) of the Midwest was in drought and 9 percent was in extreme drought as November came to a close. The drought has contributed to low water issues from the Great Lakes to the Missouri and Mississippi rivers to lakes and farm ponds. Navigation on the Mississippi River is a growing concern as levels continued to drop through November. In Iowa near Des Moines, Saylorville Reservoir fell to within inches (cm) of its record low stage. Recharge of soil moisture also is a concern with the low precipitation totals.
  • Severe weather hit the Midwest on only one day in the month. Among the severe weather that occurred that day were rare November tornadoes that touched down in Minnesota. Three weak tornadoes damaged trees, power lines, and some roofs in the greater Minneapolis-St. Paul area. It was just the 4th time on record that Minnesota had tornadic weather in November. The most recent occurrence was in 2000 and the latest in the season was on November 16, 1931 (The official NOAA tornado dataset only dates back to January 1950). In addition to the tornadoes in Minnesota, many locations in the state reported strong thunderstorm winds. Large hail was also recorded in Illinois that day.
  • 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)
  • Mean temperatures in November were below normal across most of the Southeast region, except across Puerto Rico and the U.S. Virgin Islands, where monthly temperatures were between 1 and 3 degrees F (0.5 and 1.6 degrees C) above normal. The greatest departures were found across coastal sections of the Carolinas and Virginia, where monthly temperatures were between 5 and 6 degrees F (2.8 and 3.3 degrees C) below normal. Wilmington, NC (period of record 1870-2012) and Charleston, SC (period of record 1938-2012) recorded their fourth and fifth coldest Novembers on record, respectively. Most other locations across the region were between 3 and 4 degrees F (1.6 and 2.2 degrees C) below normal, except across northern section of Florida, Alabama and South Carolina, and western sections of North Carolina, where monthly temperatures were between 1 and 2 degrees F (0.5 and 1.1 degrees C) below normal. The warmest weather occurred during the first half of the month, with temperatures exceeding 80 degrees F (26.7 degrees C) across parts of Alabama, Georgia, and South Carolina from the 3rd to the 5th of the month. Temperatures reached 70 degrees F (21.1 degrees C) as far north as northern Virginia from the 11th to the 13th of the month. A cold spell occurred in between these periods over a large portion of region, with subfreezing temperatures recorded as far south as southern Alabama from the 6th to the 8th of the month. Over 200 daily low maximum temperature records were tied or broken across the region during this three-day period. The coldest weather of the month occurred over Thanksgiving weekend, with subfreezing temperatures recorded as far south as central Florida on the 25th of the month.
  • November was an exceptionally dry month across the Southeast, as over 100 locations recorded one of their top five driest Novembers on record. Many of these locations recorded less than 2 inches (50.8 mm) of precipitation for the month, or less than 50 percent of normal. The driest locations were found across Florida, where monthly totals were less than 10 percent of normal in many places. Two locations in Florida Moore Haven Lock and Inverness did not record any measurable rainfall for the month. Gainesville, FL (period of record 1890-2012) recorded its second driest November with only 0.05 inches (1.27 mm), while Tallahassee, FL recorded its fourth driest November with 0.34 inches (8.64). Precipitation was between 10 and 25 percent of normal across southern Alabama, North Carolina, and eastern Virginia. Greensboro, NC (period of record 1892-2012) recorded its driest November on record with 0.24 inches (6.10 mm), breaking the previous record of 0.27 inches (6.86 mm) set in 1922, while Richmond, VA (period of record 1887-2012) recorded its fourth driest November with 0.27 inches (6.86 mm). Monthly precipitation was also below normal across most of Puerto Rico and the U.S. Virgin Islands. In contrast, some locations across coastal sections of South Carolina and southeast North Carolina recorded near normal precipitation for the month. Between 2 and 5 inches (50.8 and 127 mm) of snowfall was recorded across the higher elevations of western North Carolina during the cold spell from the 6th to the 8th of the month.
  • There were only 11 reports of severe weather across the Southeast in November, all coming on the 4th of the month across central and eastern sections of South Carolina. Strong winds brought down several trees in parts of Colleton and Hampton Counties, while quarter size hail up to two inches deep was recorded at Murrells Inlet in Georgetown County. No tornadoes were reported.
  • The lack of rainfall in November resulted in an expansion of drought conditions across the Southeast. By the end of the month, nearly 70 percent of the region was classified as abnormally dry or in drought according to the U.S. Drought Monitor, up from 40 percent at the end of October. The biggest changes were an expansion of moderate drought (D1) into central North Carolina and Virginia and the re-emergence of abnormally dry (D0) and moderate drought conditions across the Florida Panhandle. Areas of severe to exceptional drought (D2 to D4) across central Georgia expanded slightly across the state and into parts of eastern Alabama by the end of the month. The persistent dryness across Georgia continued to place stress on water supplies. Lake Lanier, which is the primary water supply for Atlanta, reached its lowest level since March 2009. The U.S. Army Corps of Engineers reported a drop of almost 4.5 feet (1.4 m) in November, which is the largest one month decline in more than five years. Releases from several reservoirs were modified in response to the dryness across North Carolina and mandatory water restrictions began to be implemented. Although the dry weather aided farmers in completing their harvests for the season, the lack of rainfall and cool temperatures affected the growth of cool season forages, and several small grain crops have been slow to germinate due to the lack of moisture. Some farmers were concerned that these crops may have difficulty surviving the winter if their growth remains stunted.
  • 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)
  • November 2012 was warm and dry across the majority of the High Plains Region. Below normal temperatures were confined to northern North Dakota where temperature departures ranged from 2.0-4.0 degrees F (1.1-2.2 degrees C) below normal. However, most locations in the Region had average temperatures at least 2.0 degrees F (1.1 degrees C) above normal. The largest departures occurred in southern Wyoming where a large area had average temperatures which were 6.0-10.0 degrees F (3.3-5.6 degrees C) above normal. The warmth caused many locations in that area to rank in the top 10 warmest Novembers on record. Laramie, Wyoming had its 3rd warmest November on record with an average temperature of 38.0 degrees F (3.3 degrees C) which was 8.7 degrees F (4.8 degrees C) above normal. The record of 40.6 degrees F (4.8 degrees C) was set in 1949 (period of record 1948-2012). Temperatures for the year continued to be among the warmest on record for locations in each state of the Region. For instance, Omaha, Nebraska had its warmest January-November on record with an average temperature of 58.4 degrees F (14.7 degrees C). The old record of 57.9 degrees F (14.4 degrees C) was set in 1934 (period of record 1871-2012). Topeka, Kansas also had its warmest January-November with an average temperature of 62.1 degrees F (16.7 degrees C). This easily beat the old record of 61.0 degrees F (16.1 degrees C), which was also set in 1934 (period of record 1887-2012).
  • Unfortunately November was another dry month as precipitation totals were still well below normal across the majority of the Region. A large swath extending from Colorado and Kansas up into southern North Dakota received as little as 25 percent of normal precipitation. In addition, some locations did not receive any measurable precipitation. For instance, Goodland, Kansas received just a trace of precipitation this month and tied with 1959, 1939, and 1932 for its driest November on record (period of record 1895-2012). Goodland has been experiencing exceptional drought conditions (D4) since the end of July. A few areas of the Region did get ample precipitation this month including northern and central North Dakota and north-central Wyoming. Williston, North Dakota had its 5th snowiest November on record with 16.0 inches (41 cm). 8.0 inches (20 cm) of Williston’s monthly total fell all in one day - the 10th. This total smashed the old daily record of 2.2 inches (6 cm) set in 1996 and 1940, and was also the 3rd highest snowfall total for any day in November (period of record 1894-2012). Although drought conditions were downgraded in parts of North Dakota where beneficial precipitation fell, the drought continued to have impacts elsewhere. For example, the Fern Lake Fire in Rocky Mountain National Park has burned for more than 6 weeks due to the combination of high winds and dry conditions. According to the Coloradoan, by the end of the month, more than 3,500 acres had burned since the fire started on October 9th. Even though the harvest season has come to a close, the dry weather continued to impact agriculture across the Region as well. The major concerns were the condition of winter wheat and the replenishment of soil moisture. According to the United States Department of Agriculture (USDA), the winter wheat ratings across the U.S. were the worst since 1985. Winter wheat emergence was still just behind the 5-year average in Colorado, Nebraska, and South Dakota. The two hardest hit states were Nebraska and South Dakota, where the percentage of the winter wheat crop rated in good condition was only 14 and 2, respectively. Neither state’s crop was rated in excellent condition.
  • According to the U.S. Drought Monitor, drought conditions remained widespread over the past month. Overall, about 94 percent of the Region was still in moderate (D1) to exceptional (D4) drought. This was down slightly from the end of last month when 98 percent of the Region was in D1-D4. Although Nebraska had a very slight improvement over last month, it was still the hardest hit state in the Region, with 77 percent in the D4 designation. Wyoming had a slight increase in D4 in the eastern portion of the state as well. Unfortunately, there were slight improvements in only limited parts of the Region. North Dakota received beneficial precipitation which led to improvements in the north-central part of the state where much of the D1 was downgraded to abnormally dry conditions (D0). By the end of the month a couple of areas of western and central North Dakota were completely drought free. According to the U.S. Seasonal Drought Outlook released November 15th, drought conditions were expected to improve across North Dakota and far northern South Dakota. All other areas of drought in the Region were expected to persist through the end of February 2013.
  • For more information, please go to the High Plains Regional Climate Center Home Page.
  • Southern Region: (Information provided by the Southern Regional Climate Center)
  • November temperature averages in the Southern Region were split longitudinally down the middle, with the western half of the region experiencing a warmer than average month, while the eastern half experienced a colder than average month. In the western half, temperatures ranged from as high as 4 to 6 degrees F (2.22 to 3.33 degrees C) above normal, while in Mississippi and Tennessee, temperatures averaged between 2 to 4 degrees F (1.11 to 2.22 degrees C) below normal. Within the central portion of the region, temperature averages remained within about 2 degrees F (1.11 degrees C) of normal either way. For the Southern Region, it is the warmest year-to-date (January to November) on record (1895-2012). The year-to date average for the region is 67.31 degrees F (19.62 degrees C). For Texas, it was the fourteenth warmest November on record (1895-2012) with a state wide temperature average of 58.80 degrees F (14.89 degrees C). Oklahoma averaged 51.60 degrees F (10.89 degrees C), which was their nineteenth warmest November on record (1895-2012). The remaining four states all averaged cooler than normal. The states averages are as follows: Arkansas averaged 49.80 degrees F (9.89 degrees C), Louisiana averaged 56.80 degrees F (13.78 degrees C), Mississippi averaged 51.40 degrees F (10.78 degrees C), and Tennessee averaged 45.60 degrees F (7.56 degrees C). For Mississippi, it was the twenty-first coldest November on record (1895-2012), while for Tennessee it was the twenty-seventh coldest November (1895-2012). The other state rankings fell in the middle two quartiles.
  • November was a very dry month for the entire Southern Region, with a strong majority of stations averaging less than half of the monthly normal precipitation total. Collectively, it was the fourth driest November on record (1895-2012) for the region, which averaged only 0.93 inches (23.62 mm) of precipitation. All six states reported precipitation averages that rank significantly among the historical record. The state wide precipitation averages are as follows: Arkansas averaged 1.80 inches (45.72 mm), Louisiana averaged 1.69 inches (42.93 mm), Mississippi averaged 2.46 inches (62.48 mm), Oklahoma averaged 0.58 inches (14.73 mm), Tennessee averaged 1.65 inches (41.91 mm), and Texas averaged just 0.33 inches (8.38 mm). For Arkansas and Louisiana it was the twelfth driest November on record (1895-2012), while for Mississippi, it was the thirty-second driest November on record (1895-2012). Oklahoma experienced its twenty-first driest November on record (1895-2012). For Tennessee, it was the ninth driest November on record (1895-2012), while for Texas, it was the fourth driest on record (1895-2012).
  • Dry conditions in the Southern Region has not allowed for much improvement in drought status. The significant lack of November precipitation has led to widespread extreme and exceptional drought in Oklahoma and northwestern Texas. In addition, an area of severe drought is now present in the western panhandle of Texas. A one category improvement did occur in western Tennessee and northeastern Arkansas. The area, which was classified as severe drought, is now classified as moderate drought.
  • November was a rather quiet month with very little in the way of severe weather. On November 11, 2012, two tornadoes were reported in northwestern Louisiana. Both were rated as EF0 and caused little to no damage, with no injuries or fatalities.
  • In Texas, one of the biggest concerns this time of year is the winter wheat crop, and the lack of rain in the short term is taking its toll: between 40 and 45 percent of all Texas winter wheat is rated as poor or very poor and that number is increasing rapidly. Additionally, grasslands continue to dry out, making it difficult for ranchers to put their herds out. On the positive side, pecan farmers are expected to have above normal harvests this year: 67 million pounds compared to the 52 million pound average (Information provided by the Texas Office of State Climatology).
  • Surface water declines have driven many meetings and symposiums in Texas, as water supplies continue to decline during a period of recharge or maintenance, such as in Corpus Christi, whose total water supply is at 40.6 percent. The city of El Paso currently is planning to drill nine new wells to meet water demands at a cost of $3.5 million. Other plans include a new pipeline between Stillhouse Hollow and Belton Lakes, estimated to cost approximately $500 million, diverting water from the Colorado River that would normally be reserved for rice farmers, and instituting water restrictions (Information provided by the Texas Office of State Climatology).
  • In Texas, lightning has caused some damage, including two fires in Leon Valley and Lufkin early in the month. Freeze warnings following these events were issued for many regions of the state, including the year’s first in El Paso. The cooler temperatures were expected to have a positive effect on human health as mosquitoes, which had thrived during the above average fall heat, died off. West Nile Virus from mosquitoes has already claimed several lives this year (Information provided by the Texas Office of State Climatology).
  • For more information, please go to the Southern Regional Climate Center Home Page.
  • Western Region: (Information provided by the Western Regional Climate Center)
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  • While most of the conterminous United States remained drier than normal this month, several systems delivered above average precipitation to portions of the Northwest. Over the last few days of November, a series of atmospheric rivers, narrow filaments of high water vapor transport with subtropical origins, brought heavy precipitation to northern and central California as well as parts of Oregon and Idaho. Throughout the West, average monthly temperatures remained above normal with many locations reporting a positive anomaly of at least 3.0 F (1.6 C).
  • Dry and warm conditions prevailed for much of the Southwest this month. Phoenix, Arizona saw its second warmest November on record at an average 68.4 F (20.2 C). Records at Phoenix began in 1895. In Colorado, Denver airport received only 1.7 in (43 mm) of snowfall this month, 20% of its normal 8.7 in (223 mm). In the Great Basin, Las Vegas, Nevada recorded its 3rd warmest November at 60.1 F (15.6 C) in a record dating back to 1937 and Ely, Nevada logged its 4th warmest November at 39.8 F (4.3 C), 6.1 F (3.4 C) above normal. Tonopah, Nevada tied 1995 for warmest autumn on record with a September-October-November average of 56.0 F (13.3 C). Records in Tonopah began in 1902. Throughout New Mexico, year-to-date average temperatures have been some of the highest on record. The January-November average temperature in Albuquerque was 62.0 F (16.7 C), the warmest such period in a record beginning in 1914. Roswell and Clayton also saw near-record year to date average temperatures. In addition, Clayton experienced its driest January-November period, receiving only 7.4 in (188 mm) so far this year and no precipitation this month. Normal January-November precipitation at Clayton is 15.43 in (392 mm) and records began in 1896.
  • The Northwest was dominated by wet and warm conditions. Between November 28-30, 3-day precipitation totals farther south at windward locations in California’s Coast Range between Big Sur and the San Francisco Bay Area were over 6 in (152 mm). This event brought monthly totals to over 200% of normal at some locations. Farther inland, some of the highest 3-day totals in the southern Cascades and northern Sierra Nevada were over 8 in (203 mm). Several long-standing daily precipitation records were surpassed in northern California and Oregon. Mt. Shasta City, California received 3.89 in (99 mm) on November 29, shattering the previous record of 1.81 in (46 mm) set in 1932. Medford, Oregon received 2.22 in (56 mm) on the 29th, breaking the daily record of 1.25 in (32 mm) set in 1917. Some of the highest daily totals were 5.1 in (130 mm) on the 30th at Big Sur, and 5.41 in (137 mm) at the Mt. Shasta RAWS on the 29th. Further north, Seattle, Washington recorded its 4th wettest November on record with a total of 9.17 in (233 mm) and also its 9th warmest at an average 47.4 F (8.6 C) for the month. Several other western Washington locations also recorded top 10 warmest November temperatures. Above normal monthly precipitation totals were also observed throughout Montana, providing relief from persistent dry conditions this year. For the year-to-date, 2012 was the warmest on record at Billings with an average 53.3 F (11.8 C) and also the driest at a total 6.86 in (174 mm). Records at Billings began in 1934. Miles City, Montana and Sheridan, Wyoming also experienced top 10 warmest and driest conditions year-to-date on record.
  • Dry conditions persisted in Hawaii. Following its driest October in a record beginning in 1950, Lihue, Kauai received only 0.58 in (14.7 mm) this month and tied 1968 for the driest November on record. Stations throughout the state recorded below normal precipitation, with percentages of normal as low as 9% in Honolulu. At the end of November, the entirety of the state was experiencing some level of drought.
  • November 18-19: Western Oregon and Washington high winds: The passing of a cold front brought high winds to western Oregon and Washington. Some of the highest wind gust speeds were recorded in southwestern Washington on the morning of the 19th. Naselle Ridge recorded 114 mph (184 kph) and at Megler Tower winds gusted to 101 mph (163 kph). At the Columbia River Bar, 97 mph (156 kph) was recorded. The high winds downed trees and power lines and caused one fatality.
  • November 29-30: High winds in San Francisco Bay Area: Another passing cold front brought strong winds to the Bay Area. Wind speeds reached 84 mph (135 kph) in Los Gatos, California and 76 mph (122 kph) in San Jose, California. San Francisco airport recorded winds near 50 mph (80 kph). High winds were also recorded in the along the Sierra crest and foothills and along the eastern Sierra and western Nevada
  • November 18-27: Dense radiation fog in California’s Central Valley: After precipitation on the 15-18th saturated the soil, clear skies and light winds created excellent conditions for the development of radiation fog in the Central Valley. On the morning of November 27th, dense fog near Chowchilla, California brought visibility down to 300 ft (91 m). A multi-car accident with 3 fatalities occurred in the heavy fog conditions.
  • 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 November 2012 was 0.67°C (1.21°F) above the 20th century average of 12.9°C (60.4°F). This is the fifth warmest November since records began in 1880. Including this November, the 10 warmest Novembers have occurred in the past 12 years.

  • The globally-averaged land surface temperature for November 2012 was the sixth warmest November on record, at 1.13°C (2.03°F) above average. The globally-averaged ocean surface temperature was also sixth warmest on record, at 0.50°C (0.90°F) above average.

  • ENSO-neutral conditions continued in the eastern equatorial Pacific Ocean during November 2012. Neutral conditions are expected to last through the Northern Hemisphere winter 2012/13 and into spring 2013.

  • The average combined global land and ocean surface temperature for September–November 2012 was 0.67°C (1.21°F) above the 20th century average of 14.0°C (57.1°F), marking the second warmest September–November on record, behind 2005.

  • The globally-averaged land surface temperature for September–November 2012 was the third warmest September–November on record, at 1.03°C (1.85°F) above average. The Southern Hemisphere land temperature was record warm for the period.

  • The combined global land and ocean average surface temperature for January–November 2012 was the eighth warmest such period on record, at 0.59°C (1.06°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 November 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 November 2012 height and anomaly mapNovember 2012 and the September–November 2012 height and anomaly mapSeptember–November 2012 maps—are generally reflected by areas of positive and negative temperature anomalies at the surface, respectively.

November

The average November temperature across land and ocean surfaces around the world was 0.67°C (1.21°F) above the 20th century average, marking the fifth warmest November since records began in 1880. Monthly global temperature anomalies have been among the five highest for their respective months for eight consecutive months, since April 2012. Including this November, the 10 warmest Novembers have occurred in the past 12 years. The 10 coolest Novembers on record all occurred prior to 1920. November 2012 also marks the 36th consecutive November and 333rd consecutive month with global temperature higher than the long-term average. The last month with a below average temperature was February 1985, nearly 28 years ago.

Most of the world's ocean surfaces were warmer than average, with record warmth observed in regions of the southeastern and northeastern North Atlantic Ocean and several Arctic seas. Most of the Indian Ocean was much warmer than average. In keeping with a years-long negative phase of the Pacific Decadal Oscillation, the northeastern Pacific Ocean remained cooler than average. Part of the central South Atlantic Ocean and west central Pacific Ocean were also cooler than average. ENSO neutral conditions were present across the eastern equatorial Pacific Ocean, with temperatures slightly above average. On balance, the global ocean temperature was 0.50°C (0.90°F) above the 20th century average, marking the sixth warmest November on record. ENSO-neutral conditions are favored through winter 2012/13 and into spring 2013, according to NOAA's Climate Prediction Center.

The globally-averaged land surface temperature for November was the sixth warmest on record, at 1.13°C (2.03°F) above average. The greatest anomalous warmth was observed across parts of far eastern Russia, where temperatures were at least 5°C (9°F) above average for the month. Much warmer-than-average November temperatures, and even record warmth in several regions, were observed across the western United States, Mexico, Central and South America, eastern Russia, southeastern and western Asia, Australia, and most of Africa and Europe. Due to the near universal anomalous warmth in the Southern Hemisphere (with the exception of New Zealand), that region of the world observed its warmest November on record. In the Northern Hemisphere, cooler-than-average temperatures occurred across parts of central Asia, part of the eastern United States, and much of Alaska and western Canada. Nonetheless, the Northern Hemisphere land surface temperature ranked as the eighth warmest on record for November.

Select national information is highlighted below:

  • According to the Australian Bureau of Meteorology, the average November maximum temperature was the fourth highest in the 63-year period of record, at 1.73°C (3.11°F) above the 1961–1990 average, while the average minimum temperature was the eighth highest on record, at 0.83°C (1.49°F) above average. No state or territory had a maximum or minimum monthly temperature below the long-term average. The maximum temperature in South Australia was the second warmest November on record, at 3.07°C (5.53°F) above average, just 0.03°C (0.05°F) below the record warmth of 1982.

  • In New Zealand, the national average temperature for November 2012 was 0.9°C (1.6°F) below the 1971–2000 monthly average, with records dating back to 1909. It was the coldest November on record for Te Kuiti on the North Island and for Cape Campbell on South Island.

  • The November monthly temperature ranged from 1.7 to 2.7°C (3.1 to 4.9°F) above average across the Republic of Moldova, a 1-in-5 year event according to the country's national meteorological service, Serviciul Hidrometeorologic de Stat.

  • November temperatures across Hungary ranged from about 2 to 4°C above average, with the greatest anomalous warmth observed in the southeast and western half of the country.

  • Austria was 2.3°C (4.1°F) warmer than the 1971–2000 average. The regions of Lower Carinthia, southern Styria, and Burgenland were 3 to 4°C (5 to 7°F) above average. No region in Austria was cooler than average for the month.

  • Temperatures ranged from 2.4 to 4.4°C (4.3 to 7.9°F) above the 1961–1990 average across Croatia during November. Northwestern and eastern Croatia were "very warm" (91st–98th percentile) while most of central and southern Croatia were "extremely warm" (greater than 98th percentile), as categorized by the country's national meteorological service, Drzavni hidrometeoroloski zavod (DHMZ).

  • Temperatures were below average in South Korea during November. The nationally averaged maximum temperature was 1.9°C (3.4°F) below the 1981–2010 average, marking the fifth lowest November maximum temperature since national records began in 1973.

November Anomaly Rank
(out of 133 years)
Records
°C °F Year(s) °C °F
Global
Land +1.13 ± 0.11 +2.03 ± 0.20 Warmest 6th 2010 +1.62 +2.92
Coolest 128th 1892 -0.98 -1.76
Ocean +0.50 ± 0.04 +0.90 ± 0.07 Warmest 6th 1997 +0.56 +1.01
Coolest 128th 1909 -0.49 -0.88
Land and Ocean +0.67 ± 0.07 +1.21 ± 0.13 Warmest 5th 2004 +0.75 +1.35
Coolest 129th 1907 -0.53 -0.95
Northern Hemisphere
Land +1.11 ± 0.12 +2.00 ± 0.22 Warmest 8th 2010 +2.05 +3.69
Coolest 126th 1892 -1.23 -2.21
Ocean +0.55 ± 0.05 +0.99 ± 0.09 Warmest 4th 2006 +0.67 +1.21
Coolest 130th 1909, 1912 -0.52 -0.94
Ties: 1997, 2009
Land and Ocean +0.76 ± 0.08 +1.37 ± 0.14 Warmest 6th 2010 +1.05 +1.89
Coolest 128th 1892 -0.75 -1.35
Southern Hemisphere
Land +1.15 ± 0.11 +2.07 ± 0.20 Warmest 2nd 2009 +1.18 +2.12
Coolest 132nd 1917 -0.75 -1.35
Ocean +0.48 ± 0.04 +0.86 ± 0.07 Warmest 4th 1997 +0.57 +1.03
Coolest 130th 1909, 1910 -0.45 -0.81
Ties: 2002
Land and Ocean +0.58 ± 0.06 +1.04 ± 0.11 Warmest 3rd 2009 +0.64 +1.15
Coolest 131st 1910 -0.49 -0.88
Seasonal (September–November)


The average September–November seasonal temperature across the world's land and ocean surfaces was second warmest on record, behind 2005, at 0.67°C (1.21°F) above the 20th century average. With ENSO-neutral conditions present during all three months in the eastern and central equatorial Pacific Ocean, the globally-averaged ocean temperature was the fourth warmest for September–November, with record warm temperatures observed in parts of the northeastern and southern North Atlantic Ocean and parts of the western Indian Ocean.

Globally, the average land surface temperature was the third warmest September–November on record, behind 2005 and 2010. The Southern Hemisphere spring temperature was record warm, while the average Northern Hemisphere fall land temperature was fifth warmest. Record high temperatures for the period were observed in parts of both hemispheres, including the southwestern United States, part of northern Africa and southern Europe, regions in far eastern Russia, part of north central Australia, and swaths of central and northern South America. No seasonal record cold temperatures were observed during this period.

Select national information is highlighted below:

  • Nationally, Australia reported its second warmest September–November (Southern Hemisphere spring) maximum temperature, behind 2006, since records began in 1950, at 1.73°C (3.11°F) above the 1961–1990 average. South Australia and the Northern Territory were both record warm.

  • The United Kingdom observed its coolest fall since 1993, with the average temperature 0.8°C (1.4°F) below the 1981–2010 average.

  • Owing to a warmer-than-normal September and November and a near-average October, the September–November period was 1.2°C (2.2°F) above the long-term average across Austria, according to the country's national meteorological agency, ZAMG. The country's mountain regions were 1.9°C (3.4°) above average, marking the third warmest such period in this area since records began in 1851.

  • The September–November temperature for the Republic of Belarus was 1.8°C (3.2°F) above the long-term average, a 1-in-20 year event according to the nation's meteorological agency, Pagoda.

  • Temperatures ranged from 1.4 to 2.6°C (2.5 to 4.7°F) above the 1961–1990 average across Croatia during September–November. Most of the country was "very warm" (91st–98th percentile) while some areas in northeastern and central Croatia were "extremely warm" (greater than 98th percentile), as categorized by the country's national meteorological service, Drzavni hidrometeoroloski zavod (DHMZ).

September–November Anomaly Rank
(out of 133 years)
Records
°C °F Year(s) °C °F
Global
Land +1.03 ± 0.18 +1.85 ± 0.32 Warmest 3rd 2005 +1.20 +2.16
Coolest 131st 1881 -0.79 -1.42
Ocean +0.53 ± 0.04 +0.95 ± 0.07 Warmest 4th 2003 +0.57 +1.03
Coolest 130th 1909 -0.46 -0.83
Land and Ocean +0.67 ± 0.09 +1.21 ± 0.16 Warmest 2nd 2005 +0.69 +1.24
Coolest 132nd 1912 -0.52 -0.94
Northern Hemisphere
Land +1.04 ± 0.18 +1.87 ± 0.32 Warmest 5th 2005 +1.36 +2.45
Coolest 129th 1912 -0.97 -1.75
Ocean +0.58 ± 0.04 +1.04 ± 0.07 Warmest 4th 2006 +0.65 +1.17
Coolest 130th 1912 -0.53 -0.95
Land and Ocean +0.75 ± 0.11 +1.35 ± 0.20 Warmest 3rd 2005 +0.87 +1.57
Coolest 131st 1912 -0.69 -1.24
Ties: 2003
Southern Hemisphere
Land +1.02 ± 0.15 +1.84 ± 0.27 Warmest 1st 2012 +1.02 +1.84
Coolest 133rd 1905 -0.56 -1.01
Ocean +0.50 ± 0.04 +0.90 ± 0.07 Warmest 4th 1997 +0.58 +1.04
Coolest 130th 1910 -0.44 -0.79
Land and Ocean +0.59 ± 0.07 +1.06 ± 0.13 Warmest 2nd 1997 +0.62 +1.12
Coolest 132nd 1910 -0.45 -0.81
Ties: 2009

Year-to-date (January–November)

The average global temperature across land and ocean surfaces for the year to date (January–November) resulted in the eighth warmest such period on record, at 0.59°C (1.06°F) above the 20th century average. This anomaly is slightly higher than last month's year-to-date value (January–October). The 2012 year-to-date temperature departure from average has increased each month since February. The warmth is due in large part to the monthly land surface temperatures throughout most of the year. Since April, each month has ranked among the top eight for its respective month, with May and June having record high temperatures. Additionally, the weak-to-moderate La Niña that was present at the beginning of the year had dissipated by April, with above-average ENSO neutral conditions prevailing by July. If this anomalous warmth continues through the end of the year, 2012 will surpass 2011 as the warmest La Niña year since at least 1950, according to NOAA's Climate Prediction Center.

Very few regions of the world were cooler than average for the year to date, primarily most of Alaska and parts of the northeastern and central Pacific Ocean. These cool ocean temperatures are associated with the Pacific Decadal Oscillation, which has been in a persistent negative (cold) phase since mid-2010.

January–November Anomaly Rank
(out of 133 years)
Records
°C °F Year(s) °C °F
Global
Land +0.96 ± 0.20 +1.73 ± 0.36 Warmest 5th 2010 +1.12 +2.02
Coolest 129th 1884 -0.64 -1.15
Ocean +0.45 ± 0.03 +0.81 ± 0.05 Warmest 9th 1998 +0.53 +0.95
Coolest 125th 1911 -0.46 -0.83
Ties: 1997, 2001
Land and Ocean +0.59 ± 0.09 +1.06 ± 0.16 Warmest 8th 2010 +0.68 +1.22
Coolest 126th 1911 -0.46 -0.83
Northern Hemisphere
Land +1.06 ± 0.26 +1.91 ± 0.47 Warmest 5th 2007, 2010 +1.24 +2.23
Coolest 129th 1884 -0.75 -1.35
Ocean +0.46 ± 0.04 +0.83 ± 0.07 Warmest 8th 2005 +0.56 +1.01
Coolest 126th 1910 -0.47 -0.85
Ties: 2002
Land and Ocean +0.69 ± 0.14 +1.24 ± 0.25 Warmest 4th 2010 +0.81 +1.46
Coolest 130th 1912, 1913 -0.47 -0.85
Ties: 2002
Southern Hemisphere
Land +0.69 ± 0.12 +1.24 ± 0.22 Warmest 8th 2005 +0.90 +1.62
Coolest 126th 1917 -0.65 -1.17
Ocean +0.45 ± 0.03 +0.81 ± 0.05 Warmest 11th 1998 +0.55 +0.99
Coolest 123rd 1911 -0.49 -0.88
Land and Ocean +0.49 ± 0.06 +0.88 ± 0.11 Warmest 9th 1998 +0.60 +1.08
Coolest 125th 1911 -0.50 -0.90

The most current data November 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 anomaly values based on the GHCN dataset of land surface stations using a base period of 1961–1990. As is typical, precipitation anomalies during November 2012 and September–November 2012 varied significantly around the world.

  • As a whole, the United Kingdom observed precipitation that was 111 percent of the 1981–2010 average during November. Parts of southwest to northeast England saw more than 150 percent of average precipitation, primarily due to a series of low pressure systems that brought heavy rainfall and subsequent flooding to the area within a one-week period.

  • Spain was also wetter than average for November, receiving 150 percent of average total precipitation for the month.

  • According to the Bureau of Meteorology, Australia was drier than average during September–November, with only Western Australia reporting above-average rainfall. The Indian Ocean dipole, a climate pattern that influences precipitation patterns across the continent, was positive during much of the period. This phase is generally associated with below-average rainfall across parts of southern, central, and northern Australia, as was observed.

  • South Korea received its fourth highest September–November precipitation total since records began in 1973. Rainfall was 142 percent of normal for the period.

Additional details on flooding and drought events around the world can also be found on the November 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 14 December 2012

November 2012Wildfires sparked at north and south edges of Australia. read more November 2012Heatwaves warmed eastern cities of Argentina and Australia. read more November 2012Torrential rains inundated parts of Europe. read more November 2012Typhoon Bopha devastated the Philippines read more

Drought and Wildfires

Fires in northern Australia during November 2012
Fires in northern Australia
during November 2012
Source: NASA Earth Observatory

The tropical savannas of northern Australia — where the country's largest and most frequent fires ignite — experienced the increase of bushfires associated with the latter part of the spring. The flammability potential of the dry season for the northern region typically peaks in November. Because the northern region's dried grasses, twigs, and leaves are subject to continuous decomposition by fungi and bacteria, the fires in the Cape Fear Peninsula woodlands tend to be less severe than ones occurring in southern Australia. Fewer fungi and bacteria exist in southern Australia, which allows leaf litter and other fuels to accumulate for decades.

Australian Rainfall Deficiencies between 1 August and 30 November 2012
Australian Rainfall Deficiencies
between 1 August and 30 November 2012
Source: Australian Bureau of Meteorology

Severe rainfall deficits persisted across much of South Australia for the August through November 2012 period. Conditions in Southern Australia, which observed the third driest spring during its 113-year period of record and a November rainfall of 54% below-average, were conducive to wildfire activity. A bushfire in South Australia on the Eyre Peninsula, which destroyed two homes, several vehicles, and at least 14 structures at a campground, burned nearly 5,000 acres of scrubland and crops, according to media reports. As many as 300 sheep perished in the blaze near Tulka and some wildlife were injured as well, before the fire was contained on November 13th. Local fire service volunteers helped to rescue koalas and kangaroos. Later in the month, as thunderstorms moved across South Australia over 31,500 lightning strikes were reported and as many as 300 fires were sparked. A 4,200-acre bushfire burning near Port Lincoln produced heavy smoke, which disrupted the bus transportation for area schools, and its flames threatened homes and electrical infrastructure. The fire was fueled by stumps and logs in an area of sugar gum trees that are indigenous to the Eyre Peninsula, which had not undergone a bushfire in about 50 years, according to media reports.

A wildfire ignited in central New Zealand on November 28th, but was quickly contained after burning only about four acres of scrubland.

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Extreme Temperatures

Several mountain locations in Bulgaria set new temperature records during the month as an autumn inversion warmed the peaks of the Stara Planina ranges, Vitosha, and Rhodope Mountains on November 13th. The daily maximum temperatures reached 11.3°C (52.3°F) at Botev Peak, 12.8°C (55.0°F) at Cherni Vrah, and 18.3°C (69.4°F) at Rozhen, according to media reports. Hot days occurred later in the month, with 15 record high temperatures being broken on November 30th. In northern Bulgaria, the city of Lovech's maximum temperature of 22.4°C (72.3°F) was a new daily record, while also being the hottest location in the country that day.

High energy demand during a heatwave in Argentina resulted in a failure of two high voltage lines, which led to a power loss for over one million homes and created major disruption of traffic in Buenos Aires on November 7th. The city experienced at least three days with temperatures above 32.2°C (90.0°F) before cooler temperatures with rain arrived. On November 8th, the minimum temperature cooled only to 25.0°C (77.0°F), according to media accounts.

Extreme Heat in eastern Australian during November 2012
Extreme Heat in eastern Australian
during November 2012
Source: Australian Bureau of Meteorology

Elsewhere in the Southern Hemisphere, another intense heatwave occurred during November in eastern Australia. Maximum temperatures were above-average for most of the country, and the exceptional spring heat across central and southeastern Australia from November 24th-30th greatly contributed to the anomalies. The country experienced its sixth-warmest November and second-warmest spring in 63 years of record. November 29th was the hottest November day on record for 18 long-term stations in the states of Victoria, New South Wales (NSW), and South Australia, at locations having between 42 and 101 years of observations. Record high minimum temperatures occurred at a number of sites along the NSW and Victoria border as well as places in Tasmania. Moist air advection triggered severe thunderstorms in western Victoria, where large hail, strong winds, and flash floods hit the city of Ballarat (located northwest of Melbourne) on November 30th. Fallen trees damaged homes and blocked roadways around the area, according to media reports.

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Flooding

Early in the month, northern France experienced heavy rains that resulted in flooding of more than 200 homes along the coast of the English Channel. As much as 50 cm (about 20 inches) of water stood in the streets of 60 towns, according to media reports. Rivers in the region of Nord Pas-de-Calais rose significantly, with the Liane River reaching its record-high level of 4.47 m (14.6 ft).

Tributaries to the Danube River overflowed their banks following days of heavy rain in south-central Europe. In Slovenia, more than 2,000 buildings were damaged by flooding, the rail transportation between Celje and Velenje was disrupted, and water systems were contaminated. On November 5th, residents were evacuated from the country's second-largest city, Maribor, as well as from several towns and villages. In northern Croatia, the Drava River flooded at least 100 homes and forced evacuation of about 300 people on November 6th.

Heavy rains in northern Italy during November 2012
Heavy rains in northern Italy
during November 2012
Source: NASA Earth Observatory

Torrential rains and wind battered parts of north and central Italy from November 10th-13th leading to devastating floods and at least four fatalities in Tuscany. About 800 residents were evacuated and thousands of households lost power, while vineyards and olive groves were swept away. The run-off produced when nearly 228 mm (9 inches) of rain dropped in four hours caused local rivers to overflow, according to media reports. Several bridges collapsed, highways between Rome and Florence were closed, and rail services between Orbetello and Grosetto were suspended as a result of the worst flooding in decades. As much as 149 cm (about 5 ft) swamped most of the city of Venice, marking the sixth-highest level since records began in 1872.

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Tropical Cyclones

The official hurricane season (June 1st-Nov 30th) came to a close in the Atlantic Basin during November. Nineteen named storms formed in 2012, which are seven more storms than the historical average. Please visit NOAA's visualization link for an animation of the 2012 hurricane activity and the Hurricanes and Tropical Storms page for detailed information.

Typhoon Bopha lashed Philippines on 03 December 2012
Typhoon Bopha lashed Philippines
on 03 December 2012
Source: NASA Earth Observatory

In the Western Pacific basin, Typhoon Bopha (a.k.a. Pablo; Nov 25th–Dec 9th) made landfall on the Philippine island of Mindanao on December 4th. Bopha formed unusually close to the equator for a storm of its strength and underwent rapid intensification during its westward approach to the southern Philippines. The Category 5 storm was the strongest ever to hit the island, which is the same region where Tropical Storm Washi casued over 1,300 fatalities in December 2011. The catastrophic cyclone, Bopha, resulted in over 900 deaths and more than 600 people missing, according to media reports. Losses of infrastructure, agriculture, and property were estimated at nearly $348 million U.S. dollars. More than 34,000 acres (roughly 20 percent) of Mindanao's banana plantations were destroyed as well as thousands of acres of coconut trees and rice fields. The Philippines are the world's third-largest banana exporter.

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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 November, much of the country was drier than average, while the western states were warmer than average, both of which limited snowfall during the month. Despite the warm and dry conditions, several storms and cold fronts did impact the mountainous West and the Northern Plains, bringing snowfall. According to NOAA’s National Snow Analysis, at the beginning of November, 3.0 percent of the contiguous U.S. had snow on the ground — the Central and Southern Appalachians, parts of the Upper Midwest, and the highest terrain of the West. Daily snow cover peaked on November 12th with 31.5 percent of the country snow covered. On November 30th, 14.4 percent of the lower 48 had snow on the ground — much of the interior Northeast, the Western Great Lakes, the Northern Plains, and the high terrain of the West.

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

According to data form the Rutgers Global Snow Lab, much of the Central Rockies, Central Plains, Midwest, and Northeast experienced below-average snow cover during November, while the Northern Rockies and Northern Plains experienced above-average snow cover. As a whole, the contiguous U.S. experienced below-average November snow cover. The monthly average snow extent of 398,000 square miles (1.03 million square km) was 53,000 square miles (137,000 square km) below the 1981-2010 average.

Summary of Notable Snow Events:
Sandy Snowfall Totals
Satellite image of Northeast snow
9 November 2012
Source: NASA

A strong, early-season Nor’easter impacted the Northeast and New England on November 7th and 8th, on the heels of post-tropical cyclone Sandy. The storm brought strong winds, storm surge, and heavy precipitation from New Jersey to Maine. Snowfall totals from the storm were generally light, but were unusual for this early in the season. Central Park in New York City received 4.7 inches of snow, marking the earliest 4.0+ inch snow accumulation for that location. The previous record was November 23rd, 1989. The highest snow accumulation occurred in Clintonville, Connecticut, which received 13.5 inches of snow. The storm was accompanied by winds in excess of 40 mph which caused power outages to 375,000 homes, many of which had just had their power returned after Sandy. Many homes were still without power when the Nor’easter hit.

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 pattern this time of year normally consists 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 and early winter, polar air masses get colder and expand the polar jet toward the south. During November 2012, several weather systems moved through the jet stream's weather patternwesterly circulation over the United States, bringing above-normal precipitation to the northwestern parts of the country. But weather patternupper-level high pressure, centered over the Southwest to central Rockies, fought back, setting up a pattern which mostly kept moisture away from the central and eastern regions and much of the Southwest. weather patternCold fronts sweeping across the Plains and into the South and East brought below-normal monthly temperatures to much of the country east of the Mississippi River, while the upper-level ridge kept temperatures warmer than normal across much of the West for most of the month. This weather pattern inhibited the formation of tornadoes, reduced the coverage of snow, and expanded the area and intensity of drought.

Monthly precipitation anomalies
Monthly precipitation anomalies.

The movement of the weather systems can be seen in the weekly precipitation anomaly patterns (weeks 1, 2, 3, 4). Frontal precipitation occurred in the West and Plains early in the month, and in the Midwest and Southeast at mid-month; but, otherwise, most of the country outside of the northwestern regions saw little precipitation. Western storms expanded snow coverage to about a third of the country by November 12th, but the snow cover rapidly contracted. All told, monthly snow cover and snow water equivalent were below average. Twenty-two states ranked in the top ten driest category for November, with another 18 ranking in the driest third of the historical record. Only Montana, North Dakota, and Oregon were in the wettest third of the historical record. With all of the dry weather, drought expanded this month. According to the end-of-November (November 27) U.S. Drought Monitor, 62.7% of the contiguous U.S. (52.4% of the U.S. including Alaska, Hawaii, and Puerto Rico) was affected by moderate to exceptional drought overall. According to the Palmer Drought Index, which goes back to the beginning of the 20th century, 59.5% of the contiguous U.S. was in moderate to extreme drought, an increase of about 7% compared to last month. The 2012 Palmer Drought Index percent area values have been exceeded only by the drought of the 1930s.

Monthly temperature anomalies
Monthly temperature anomalies.

The weekly temperature anomaly maps (weeks 1, 2, 3, 4) show the dominance of cooler air masses at mid-month and in the east early in the month, as well as the expansion of the ridge and warmer air masses later in the month as the jet stream retreated to the north. Five states ranked in the top ten warmest category for November, all in the West, while another 13 western, Great Plains, and Midwest states ranked in the warmest third of the historical record. At the opposite extreme, North Carolina ranked in the top ten coldest category with 17 other states (all east of the Mississippi River) falling in the coldest third of the historical record. On a local basis, almost three times as many record warm highs and lows occurred than record cold highs and lows. About 1800 daily high temperature records and 1300 record warm daily low temperatures were tied or broken. In comparison, about 450 record low temperatures and 600 record cool daily high 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 November 2012 that was near average.

When averaged together, the mixture of temperature and precipitation extremes gave the U.S. the 20th warmest and eighth driest November in the 118-year record. Averaging extremes tends to cancel them out. 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 (third largest PDSI component for November 2012, behind November 1954 and 1934, and 18th largest number of days without rain component), the heavy precipitation in the Far West (14th largest extremes in 1-day precipitation component), and the large spatial extent of very warm maximum (11th largest) and minimum (22nd largest) temperatures combined to give the U.S. a November USCEI that was 11th largest. The preponderance of unusual warmth and dryness for much of 2012 has ranked the national USCEI largest for the year-to-date (January-November) and last twelve months (December-November) and eighth largest for the last six months (June-November).

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 November:

  • El Niño Southern Oscillation (ENSO)
    • Status: Ocean temperatures and atmospheric circulation anomalies indicated that the equatorial Pacific continued in an ENSO-neutral state during November, although equatorial sea surface temperatures (SSTs) remained above average across much of the Pacific Ocean except for below-average SSTs in the far eastern equatorial Pacific.
    • Teleconnections (influence on weather): To the extent teleconnections are known, while in a neutral state, ENSO normally is not a player in the month's weather. Historical data can be analyzed to show typical temperature and precipitation patterns associated with the ENSO episodes. For an El Niño, the typical September-November temperature anomaly pattern is below-normal temperatures for the Southwest and patchy below-normal temperatures from the Southern Plains and Southeast to Midwest, with patchy above-normal temperatures for the Northwest. The typical El Niño September-November precipitation anomaly pattern consists of drier-than-normal conditions in the mid-Atlantic to Northeast, much of the Great Lakes, and parts of the Ohio Valley and Central Plains. Wetter-than-normal conditions usually occur in the Tennessee Valley to Southern Appalachians, with patchy wet conditions in the Great Plains and West. For a La Niña, the typical September-November temperature anomaly pattern consists of warmer-than-normal conditions from the Central Plains to the Great Lakes, and precipitation anomaly pattern is drier than normal across much of the country from the Southwest to Northeast, and all along the Mississippi River Valley, with above-normal precipitation mostly along the Northwest coast.
    • Observed: The November and September-November 2012 precipitation patterns match the La Niña teleconnections for much of the country from the West Coast to Mississippi Valley and parts of the Southeast and Northeast; the September-November patterns show some hint of correlation to El Niño's in the Tennessee Valley to mid-Appalachians, but not elsewhere. The November and September-November 2012 temperature patterns agree with El Niño for the Southeast, but not elsewhere, and don't agree with the La Niña teleconnections.
  • The Pacific/North American (PNA) pattern
    • Status: The PNA index was near zero at the beginning of the month then trended negative for the rest of November.
    • Teleconnections (influence on weather): To the extent teleconnections are known, the temperature teleconnection map for this time of year (October on the maps) shows that a negative PNA is correlated with warmer-than-normal temperatures in the Southeast and cooler-than-normal temperatures along the west coast of North America, especially in western Canada and Alaska. The precipitation patterns are weakly correlated this time of year, but show some hint of wetter-than-normal conditions from the Ohio Valley to Great Lakes with a negative PNA.
    • Observed: November 2012 was wetter than normal in the Northwest and drier than normal across the rest of the country, which bears little resemblance to the pattern expected with a negative PNA. The month was generally cooler than normal east of the Mississippi River and warmer than normal west of it, with cooler than normal temperatures across Alaska. The Alaska temperature pattern is consistent with that expected from a negative PNA, but the contiguous U.S. pattern more closely resembles that for a positive PNA than negative PNA.
  • The Arctic Oscillation (AO) pattern
  • The North Atlantic Oscillation (NAO) pattern
    • Status: The NAO index started the month negative, transitioned to positive, then hovered near zero but slightly negative for the last half of November.
    • Teleconnections (influence on weather): To the extent teleconnections are known, a negative NAO during this time of year (October on the teleconnection maps) is typically associated with drier-than-normal conditions in the Ohio Valley, while a positive NAO is typically wetter than normal there. Temperatures show little correlation.
    • Observed: The weak correlations this time of year make it difficult to relate the November and September-November 2012 precipitation and temperature anomaly patterns to the NAO. The temperature pattern in the eastern U.S. more closely resembles what would be expected from a negative NAO in the winter.
  • The East Pacific-North Pacific (EP-NP) pattern relates sea surface temperature (SST) and upper-level circulation patterns over the eastern and northern Pacific to temperature, precipitation, and circulation anomalies downstream over North America.
Map of three-month temperature anomalies
Map of three-month temperature anomalies.
Map of three-month precipitation anomalies
Map of three-month 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 November and September-November 2012 temperature, precipitation, and circulation patterns, suggests that it is difficult to associate the observed weather patterns to any of these indices. The teleconnections are weak this time of year for the PNA and NAO. The tropical Pacific is in a neutral ENSO phase and the AO and EP-NP were in a state of transition during November. 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.

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 November, there were 8 preliminary tornado reports. This is significantly less than the 1991-2010 average of 58 for the month. Tornado activity during November varies greatly from year to year, with the Gulf Coast states typically receiving the most November tornado occurrences. During November 2012, two of the preliminary tornado reports were in Louisiana, two in California, and four in Minnesota.

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

The below-average tornado activity during November was a continuation of a slower-than-average tornado year for the country. The preliminary number of tornadoes during January-November was 894, with 94 tornado reports still pending for September, October, and November. This marked the lowest January-November tornado count since 2002.

An unusual weather pattern for November brought severe weather to Minnesota on November 10th. As a cold front approached from the west, record warm temperature surged into the Upper Midwest. As the cold front moved through Minnesota, it spawned four weak tornadoes in the Twin Cities metro area shortly after sunset. No injuries or fatalities were reported with only light structural damage according to storm reports. This outbreak marks the latest date in the 1950-2012 period of record for a tornado touchdown in Minnesota and only the second time for a tornado to impact the state during November. The only other tornado confirmed in Minnesota in November occurred on November 1st, 2000.

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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.

This page is currently undergoing a refresh and will temporarily not be updated. The 2012 annual tropical cyclone report will be available in January 2013 and regular monthly updates will resume in spring 2013 with the start of the next North Atlantic hurricane season. We apologize for any inconvenience.

Information on current tropical cyclone activity is available through these Worldwide Tropical Cyclone Centers:

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 17 December 2012
Contents Of This Report:
Map showing Palmer Z Index

Please note that the values presented in this report are based on preliminary data. They will change when the final data are processed, but will not be replaced on these pages.
National Drought Overview

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Detailed Drought Discussion

Overview

November 2012 marked a return to the warmth and dryness which characterized much of the year, ranking as the 20th warmest and eighth driest November (based on data back to 1895) when weather conditions are averaged across the country. Like the last several months, cool fronts swept across the country (weeks 1, 2, 3, 4), bringing below-normal monthly temperatures to most areas east of the Mississippi River. High pressure (High, or upper-level ridge), centered over the Southwest and Central Rockies, dominated the West and Great Plains with its descending air ("subsidence"), resulting in a monthly pattern of anomalous warmth there. The associated circulation patterncirculation pattern dumped above-normal precipitation across parts of the West from California to the Northern Rockies and northern High Plains, but it also reduced precipitation across the rest of the country (weeks 1, 2, 3, 4). The wet weather in the West nibbled away at the edge of the drought areas in the Pacific Northwest and northern High Plains, but dry weather expanded drought in the Southeast, Southern Plains, and Hawaii. Nationally, the moderate to exceptional (D1-D4) drought footprint increased to about 52.4 percent of the country, compared to last month, while the percentage in the abnormally dry to exceptional drought category increased to about 71.2 percent. About 16.8 percent of the country was in the worst drought categories (D3-D4, extreme to exceptional drought), a bit more than last month. The Palmer Drought Index, whose data go back 113 years, is relied upon for drought comparisons before 2000. The November 2012 Palmer value of 59.5 percent in moderate to extreme drought is an increase of about 7 percent compared to last month, and the percent area in severe to extreme drought increased to about 44.8 percent.

The U.S. Drought Monitor drought map valid November 27, 2012
The U.S. Drought Monitor drought map valid November 27, 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 the November short-term drought conditions exacerbated long-term drought conditions across the nation's drought areas (November PHDI compared to October PHDI), resulting in an increase in the percent area under drought. The November short-term dryness essentially neutralized the areas of October moistness that had developed in the Northeast to Ohio Valley. The areas that received above-normal precipitation were mostly in the Northwest, which was for the most part drought-free.


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 map shows the area of November dryness covering most of the country east of the Mississippi River, the Southern and Central Plains, and the Central Rockies to Southwest. Near normal to wet conditions stretched from northern California, across the Northwest, to the Northern High Plains. Much of the Northwest (especially coastal sections) shows up as wet at all time scales. The Northeast is dry at the 1-month time scale but near normal to wet at the 2- to 24-month time scales. Dryness dominates in the Southeast at all time scales, except wet conditions are evident at 6 to 12 months along the Gulf Coast. The Ohio Valley has evidence of wet conditions at 3 and 24 months, but dry conditions at 2, 6, 9, and 12 months. Dry conditions dominate at all time scales across the Southwest to Southern and Central Plains, spreading into the Northern Plains and Midwest on the 6- to 12-month SPI maps.


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


Agricultural and Hydrological Indices and Impacts

University of Washington VIC Model soil moisture percentile
University of Washington VIC Model soil moisture percentile
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-November (November 26th) U.S. Department of Agriculture (USDA) reports, winter wheat emergence was hampered by drought in several central states, with 65 percent of the winter wheat in drought. Overall, 26 percent of the winter wheat was rated in poor to very poor condition (compared to 15 percent a month ago), although that number was much higher in South Dakota (64 percent), Nebraska (46 percent), Oklahoma (44 percent), and Texas (40 percent). About 65 percent of the domestic hay acreage and 73 percent of the domestic cattle inventory were in an area experiencing drought.

Map showing NOAA/CPC modeled monthly soil moisture percentiles
Map showing NOAA/CPC modeled monthly soil moisture percentiles.

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: November 2012 was another very dry month for the Hawaiian Islands. The pattern of below-normal rainfall was evident at most time periods (especially the last 2 months, but also the last 3, 6, 8, 12, and 36 months, year-to-date, water year-to-date, and, for the southern islands, the last 24 months), and streamflow was below normal across the islands. Moderate to extreme drought affected 54 percent of the state, a little more than last month.

Alaska: Most of the stations in Alaska were drier and cooler than normal during November. The dryness is widespread at 2 months (water year-to-date). But the pattern shifts at longer time scales, with dryness evident from the southeast panhandle to interior southeast stations (at 3, 6, and 8 months) then becoming mixed (at the year-to-date and 12-, 24-, and 36-month time scales). An area of abnormal dryness covered the northern areas to south central Alaska on the USDM map.

Puerto Rico: Southeastern Puerto Rico was drier than normal during November with a mixed precipitation pattern across the rest of the island. The pattern of dryness in the southeast is evident at longer time scales (2 months [water-year-to-date] and year-to-date, but especially the last 3 to 6 months). Except for a few gauges in the east, November monthly streamflow was generally near normal. The November 27th USDM map was free of any drought or abnormally dry areas.

CONUS State Ranks:

Current month state precipitation ranks Northeast region precipitation, November, 1895-2012

Over a third of the U.S. was very dry (the driest ten percent of the historical record) during November 2012, marking the driest November since 1976 by this measure. On a statewide basis, November 2012 ranked in the driest third of the historical record for November for 22 states — mostly east of the Mississippi — with five states (Connecticut, Florida, New Hampshire, Vermont, West Virginia) second driest in the 1895-2012 record.

3-month state precipitation ranks The spatial pattern of dryness at the three-month time scale was centered from the Southwest to Upper Midwest and in the Southeast. Three states (Nebraska, South Dakota, and Minnesota) fell in the top ten driest category for September-November 2012, while another 14 ranked in the driest third of the historical record for November.

6-month state precipitation ranks Nebraska statewide precipitation, June-November, 1895-2012

Wyoming statewide precipitation, June-November, 1895-2012

At the six-month time scale the Central Rockies to Central Plains were the epicenter of dryness, with Nebraska and Wyoming having the driest June-November in the 1895-2012 record. Eight other states (from the Southwest to the Upper Midwest) were in the top ten driest category and an additional twelve states (from the West to Midwest and in the Southeast) ranked in the driest third of the historical record for June-November.

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

The spatial pattern of dryness for the year-to-date was similar to that for the twelve-month time scale, with dryness stretching across the country from the Intermountain Basin to the East Coast. A large epicenter of dryness was located from the Central Rockies to the Midwest, with smaller ones in the Southeast and Mid-Atlantic Coast.

Colorado statewide precipitation, January-November, 1895-2012 Wyoming statewide precipitation, December-November, 1895/96-2011/12

Colorado had its driest January-November during 2012, and Nebraska and Wyoming had both their driest January-November (NE, WY) and December-November (NE, WY) in the 1895-2012 record. Eight other states ranked in the top ten driest category for the year-to-date (January-November) and another 19 were in the driest third of the historical record. A total of eight states were in the top ten driest category for the last twelve months (December-November) and another 21 were in the driest third of the historical record.


Winter Wheat Belt:


Primary Hard Red Winter Wheat Belt precipitation, January-November, 1895-2012 Primary Hard Red Winter Wheat Belt Palmer Drought Severity Index, January 1900-November 2012

As noted earlier, 26 percent of the winter wheat crop was rated in poor to very poor condition, a jump of 11 percent compared to last month. November 2012 ranked as the 13th driest November in the 1895-2012 record averaged across the Winter Wheat agricultural belt, with April-November third driest and the year-to-date eighth driest. For the smaller Primary Hard Red Winter Wheat belt, November 2012 ranked 23rd driest, October-November tenth driest, April-November second driest, and the year-to-date third driest (behind January-November 1956 and January-November 1910). 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 during 2012. While the PDSI for the Primary Hard Red Winter Wheat belt is the worst in over 50 years, the PDSI values for the droughts of the 1930s and 1950s were much more severe.


River Basins:


Missouri River Basin precipitation, January-November, 1895-2012 Mississippi River and Tributaries North of Memphis, precipitation, January-November, 1895-2012

January-November 2012 Precipitation Ranks (out of 118 years) for the Major River Basins in the Contiguous U.S.
River Basin Rank
Pacific Northwest 18th wettest
California 42nd driest
Great Basin 19th driest
Lower Colorado 18th driest
Upper Colorado driest
Rio Grande 12th driest
Texas Gulf Coast 49th driest
Arkansas-White-Red 10th driest
Lower Mississippi 47th driest
Missouri 3rd driest
Souris-Red-Rainy 34th driest
Upper Mississippi 8th driest
Great Lakes 41st driest
Tennessee 32nd driest
Ohio 16th driest
South Atlantic-Gulf 41st driest
Mid-Atlantic 33rd driest
New England 56th wettest

Several river basins have experienced unusually dry conditions during 2012, with the Upper Colorado having the driest January-November in the 1895-2012 record. As noted by the Midwest Regional Climate Center, drought has contributed to low water issues from the Great Lakes to the Missouri and Mississippi rivers, with navigation on the Mississippi River becoming a growing concern as levels continued to drop through November. The Missouri River basin had the third driest January-November in 2012 (behind 1936 and 1934), the Upper Mississippi had the eighth driest January-November, and the Ohio River basin ranked 16th driest. For the Mississippi River and all of its tributaries north of Memphis, Tennessee, January-November 2012 ranked as the third driest January-November on record, again, behind 1936 and 1934. For comparison, January-November 1988 ranked fourth driest for this basin. The aggregate PDSI for the Missouri basin reached the lowest value since the 1950s, while the aggregate PDSI for the broader Mississippi and its tributaries was the lowest since only 1988.

Western U.S.


Percent area of the Western U.S. in moderate to extreme drought, January 1900 to present, based on the Palmer Drought Index
Percent area of the Western U.S. in moderate to extreme drought, January 1900 to present, based on the Palmer Drought Index.

Like last month, beneficial precipitation fell in the northern parts of the West this month, while much of the rest of the West was drier than normal. Widespread above-normal temperatures caused the precipitation to fall more as rain than snow, resulting in a pattern of above-normal precipitation but below-normal snow water content at the high elevation (SNOTEL) stations in the north. Precipitation for high elevation and low elevation stations in the south, as well as snow water content for the high elevation locations (stations, basin averages), was generally below average. The Southwest was especially dry, both in the short term (October-November water year-to-date) and long term (last 12 months, December-November). 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, 73 percent of the West was experiencing moderate to exceptional drought at the end of November, a three percent decrease compared to October. The Palmer Drought Index percent area statistic was about 67 percent, an increase compared to last month.


Historical Analogs


Drought has affected the nation for most of 2012. The year began with 27.5 percent of the contiguous U.S. in moderate to extreme drought (based on the Palmer Drought Index) with separate drought epicenters in the Southwest to Southeast and parts of the Northwest and Upper Midwest. Drought expanded to 61.8 percent of the country by July and stretched from California to the Carolinas, and Texas to North Dakota. The percent area has stayed above 50 percent since the summer, ending at 59.5 percent in November. Although every drought is different, historical analogs to the current drought can be determined by comparing the spatial pattern and intensity of various climate indicators using statistical tools such as the correlation coefficient and mean absolute difference. In the table below, the conditions for January-November 2012 were averaged and compared to the January-November average conditions for all past years in the 1900-2012 national drought record. The top five years for each of four criteria are listed in the table, with the four criteria being:

  1. the spatial pattern and intensity of the January-November average precipitation,
  2. the spatial pattern and intensity of the January-November average PHDI,
  3. the January-November average national percent area in moderate to extreme drought, and
  4. the spatial pattern and intensity of the January-November average Palmer Z Index.
Top 5 Analog Years to 2012 (January-November) based on Four Climate Criteria
Rank* Precipitation PHDI Percent Area** Palmer Z Index
January-November 2012 Statewide Precipitation Ranks January-November 2012 January-November 2012 (47.7%) January-November 2012
1
1966 1955 1931 (47.7%) 1955
2
1988 1956 1956 (47.9%) 1988
3
1953 2000 1955 (48.0%) 1934
4
1956 1981 2002 (42.8%) 1910
5
1955 1902 1954 (53.3%) 1956
* Rank: 1 = most similar to 2012.
** (Average percent area in moderate to extreme drought for January-November of the given year.)

Two years are common in each criteria: 1955 and 1956. The average percent area in drought for these two years is almost identical to the average percent area in 2012, and the spatial pattern and intensity of the dryness (as measured by precipitation, PHDI, and Palmer Z Index) during these two years are a close match to that of 2012.

January-November 2012 statewide precipitation ranks January-November 1956 statewide precipitation ranks January-November 1955 statewide precipitation ranks

Top 5 Analog Year-Months to November 2012 based on PHDI <
Rank* PHDI
(November only)
PHDI
(any month)
Nov. 2012 PHDI Nov. 2012 PHDI
1
Nov. 1955 June 1955
2
Nov. 1956 March 1957
3
Nov. 1933 May 1955
4
Nov. 1934 April 1955
5
Nov. 1939 June 1956
* Rank: 1 = most similar to 2012.

The spatial pattern of drought (PHDI) for November 2012 was compared to the spatial pattern of drought (PHDI) for all other months in the historical record using the mean absolute difference statistical tool. In the table to the left, the top five Novembers having the closest match to November 2012 are listed in the first column, and the top five months of any of the twelve months (January-December) are listed in the second column. Again, the 1950s have the closest match, with November 1955 and November 1956 being the closest November analogs.

November 2012 PHDI map November 1955 PHDI map November 1956 PHDI map

Top 5 Analog Years to 2012
(January-November) Temperature (and Jan-Nov temperature rank, average percent area in drought)
Rank* January-November 2012
Statewide Temperature Ranks

(warmest, 47.7%)
1
1998 (3rd warmest, 8.9%)
2
2006 (4th warmest, 31.5%)
3
1921 (10th warmest, 12.8%)
4
1990 (5th warmest, 31.7%)
5
1953 (13th warmest, 32.6%)
* Rank: 1 = most similar to 2012.

The dryness during the 2012 drought was accompanied by record heat. The spatial pattern of January-November average temperature for 2012 was compared to the spatial pattern of January-November average temperature for all other years in the historical record using the mean absolute difference statistical tool. The table to the right lists the top five years having the closest spatial pattern match to 2012. The year having the closest spatial pattern to January-November 2012 average temperature was 1998, which was the third warmest, nationally, for January-November (behind 2012 and 1934). Most of the country, except for the Southwest, had January-November 1998 average temperatures above to much above average. But 1998 was not a drought year on a national scale, with only an average 8.9 percent of the country experiencing moderate to extreme drought. The year with the next closest spatial pattern of January-November average temperatures was 2006, which was a drought year, nationally. Like 1998, most of the country in 2006 was warmer to much warmer than average, except for the Southeast. Next was 1921, which had widespread record heat in the midwestern and eastern states, but it was not a drought year, nationally. The fourth and fifth closest spatial matches, 1990 and 1953, had widespread drought. The warmth during those two years was as widespread as in 2012, although not quite as warm. It is interesting to note that the second warmest year nationally, 1934, was a drought year — in fact, it had the greatest average January-November percent area in moderate to extreme drought (65.7%) — with record heat in the western and central states. But most of the Northeast was colder than average, which is significantly different from the 2012 spatial pattern. The sixth through ninth warmest years nationally — 2005, 2000, 1999, and 2007, respectively — had widespread warmth, but the magnitude of the warmth, spatially, was not as severe as 2012 or the other years.

January-November 2012 statewide temperature ranks January-November 1998 statewide temperature ranks January-November 2006 statewide temperature ranks

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, November 2012 was warm and dry across the majority of the High Plains region. Temperatures for the year continued to be among the warmest on record for locations in each state of the region. Precipitation totals for November were well below normal across the majority of the region. A large swath extending from Colorado and Kansas up into southern North Dakota received as little as 25 percent of normal precipitation. In addition, some locations did not receive any measurable precipitation. For instance, Goodland, Kansas received just a trace of precipitation this month and tied with 1959, 1939, and 1932 for its driest November on record (period of record 1895-2012). Goodland has been experiencing exceptional drought conditions (D4) since the end of July. A few areas of the region did get ample precipitation this month including northern and central North Dakota and north-central Wyoming. Although drought conditions were downgraded in parts of North Dakota where beneficial precipitation fell, the drought continued to have impacts elsewhere. For example, the Fern Lake Fire in Rocky Mountain National Park has burned for more than 6 weeks due to the combination of high winds and dry conditions. According to the Coloradoan, by the end of the month, more than 3,500 acres had burned since the fire started on October 9th. Even though the harvest season has come to a close, the dry weather continued to impact agriculture across the region as well. The major concerns were the condition of winter wheat and the replenishment of soil moisture. According to the United States Department of Agriculture (USDA), the winter wheat ratings across the U.S. were the worst since 1985. Winter wheat emergence was still just behind the 5-year average in Colorado, Nebraska, and South Dakota. The two hardest hit states were Nebraska and South Dakota, where the percentage of the winter wheat crop rated in good condition was only 14 and 2 percent, respectively. Neither state's crop was rated in excellent condition.

According to the USDM, drought conditions remained widespread over the past month. Overall, about 94 percent of the region was still in moderate (D1) to exceptional (D4) drought. This was down slightly from the end of last month when 98 percent of the region was in D1-D4. Although Nebraska had a very slight improvement over last month, it was still the hardest hit state in the region, with 77 percent in the D4 designation. Wyoming had a slight increase in D4 in the eastern portion of the state as well. Unfortunately, there were slight improvements in only limited parts of the region. North Dakota received beneficial precipitation which led to improvements in the north-central part of the state where much of the D1 was downgraded to abnormally dry conditions (D0). By the end of the month a couple of areas of western and central North Dakota were completely drought free.

As explained by the Southern Regional Climate Center, November was a very dry month for the entire Southern region, with a strong majority of stations averaging less than half of the monthly normal precipitation total. Collectively, it was the fourth driest November on record (1895-2012) for the region, which averaged only 0.93 inch (23.62 mm) of precipitation. November temperature averages in the Southern region were split longitudinally down the middle, with the western half of the region experiencing a warmer than average month, while the eastern half experienced a colder than average month. The dry conditions in the Southern region have not allowed for much improvement in drought status. The significant lack of November precipitation led to widespread extreme and exceptional drought in Oklahoma and northwestern Texas. In addition, an area of severe drought was now present in the western panhandle of Texas. A one category improvement did occur in western Tennessee and northeastern Arkansas. The area, which was classified as severe drought, was now classified as moderate drought.

In Texas, one of the biggest concerns this time of year is the winter wheat crop, and the lack of rain in the short term is taking its toll: between 40 and 45 percent of all Texas winter wheat is rated as poor or very poor and that number is increasing rapidly. Additionally, grasslands continue to dry out, making it difficult for ranchers to put their herds out. On the positive side, pecan farmers are expected to have above normal harvests this year: 67 million pounds compared to the 52 million pound average (Information provided by the Texas Office of State Climatology). Surface water declines have driven many meetings and symposiums in Texas, as water supplies continue to decline during a period of recharge or maintenance, such as in Corpus Christi, whose total water supply is at 40.6 percent. The city of El Paso currently is planning to drill nine new wells to meet water demands at a cost of $3.5 million. Other plans include a new pipeline between Stillhouse Hollow and Belton Lakes, estimated to cost approximately $500 million, diverting water from the Colorado River that would normally be reserved for rice farmers, and instituting water restrictions (Information provided by the Texas Office of State Climatology).

As summarized by the Midwest Regional Climate Center, November precipitation was below normal across the Midwest. Only small pockets of northern Minnesota and Upper Michigan reached normal for the month while all nine states had areas with less than 25 percent of normal. Most of the southeastern half of the region received less than half of their normal precipitation in November. Statewide totals in Ohio (4th), Indiana (4th), Kentucky (5th), and Michigan (7th) all ranked among the 10 driest Novembers since 1895. Fall precipitation totals ranged widely from southern Illinois and northern Ohio with over 150 percent of normal to most of Minnesota with less than 50 percent of normal for the three-month period. Year-to-date statewide precipitation totals ranged from 70 percent to 95 percent of normal. Iowa (8th) and Missouri (9th) ranked among the top 10 driest January to November periods since 1895. November temperatures in the Midwest were moderate with departures ranging from 2 degrees F (1 C) along the Iowa-Minnesota border to as much as 5 degrees F (3 C) below normal in parts of eastern Kentucky. Two warm spells during the month, the first coming on the 10th to the 12th and the second on the 22nd and 23rd, were responsible for most of the 600 plus daily temperature records. Just dozens of record lows were recorded. Fall (September to November) temperatures ranged from near normal to below normal across the region. Kentucky ranked as the 6th coolest fall dating back to 1895 with temperatures 2.2 degrees F (1.2 C) below normal. The cooler November and fall temperatures have cooled the year-to-date temperatures slightly but all nine states remain among the five warmest January to November periods dating back 118 years.

Drought remained a serious issue in the western half of the Midwest. Moderate drought extended across most of the western half of the region with areas of extreme drought in Minnesota and Iowa at the end of the month. A little over half (55 percent) of the Midwest was in drought and 9 percent was in extreme drought as November came to a close. The drought has contributed to low water issues from the Great Lakes to the Missouri and Mississippi rivers to lakes and farm ponds. Navigation on the Mississippi River is a growing concern as levels continued to drop through November. In Iowa near Des Moines, Saylorville Reservoir fell to within inches (cm) of its record low stage. Recharge of soil moisture also is a concern with the low precipitation totals.

As noted by the Southeast Regional Climate Center, November was an exceptionally dry month across the Southeast, as over 100 locations recorded one of their top five driest Novembers on record. Many of these locations recorded less than 2 inches (50.8 mm) of precipitation for the month, or less than 50 percent of normal. The driest locations were found across Florida, where monthly totals were less than 10 percent of normal in many places. Two locations in Florida (Moore Haven Lock and Inverness) did not record any measurable rainfall for the month. Monthly precipitation was also below normal across most of Puerto Rico and the U.S. Virgin Islands. Mean temperatures in November were below normal across most of the Southeast region, except across Puerto Rico and the U.S. Virgin Islands, where monthly temperatures were between 1 and 3 degrees F (0.5 and 1.6 degrees C) above normal. The warmest weather occurred during the first half of the month, with temperatures exceeding 80 degrees F (26.7 degrees C) across parts of Alabama, Georgia, and South Carolina from the 3rd to the 5th of the month. Temperatures reached 70 degrees F (21.1 degrees C) as far north as northern Virginia from the 11th to the 13th of the month. A cold spell occurred in between these periods over a large portion of region, with subfreezing temperatures recorded as far south as southern Alabama from the 6th to the 8th of the month. Over 200 daily low maximum temperature records were tied or broken across the region during this three-day period. The coldest weather of the month occurred over Thanksgiving weekend, with subfreezing temperatures recorded as far south as central Florida on the 25th of the month.

The lack of rainfall in November resulted in an expansion of drought conditions across the Southeast. By the end of the month, nearly 70 percent of the region was classified as abnormally dry or in drought according to the USDM, up from 40 percent at the end of October. The biggest changes were an expansion of moderate drought (D1) into central North Carolina and Virginia and the re-emergence of abnormally dry (D0) and moderate drought conditions across the Florida Panhandle. Areas of severe to exceptional drought (D2 to D4) across central Georgia expanded slightly across the state and into parts of eastern Alabama by the end of the month. The persistent dryness across Georgia continued to place stress on water supplies. Lake Lanier, which is the primary water supply for Atlanta, reached its lowest level since March 2009. The U.S. Army Corps of Engineers reported a drop of almost 4.5 feet (1.4 m) in November, which is the largest one month decline in more than five years. Releases from several reservoirs were modified in response to the dryness across North Carolina and mandatory water restrictions began to be implemented. Although the dry weather aided farmers in completing their harvests for the season, the lack of rainfall and cool temperatures affected the growth of cool season forages, and several small grain crops have been slow to germinate due to the lack of moisture. Some farmers were concerned that these crops may have difficulty surviving the winter if their growth remains stunted.

As explained by the Northeast Regional Climate Center, despite a mid-month warm up, the Northeast was cooler than normal for November 2012. Even though it was a wet start to the month for several states, November 2012 went into the record books as the 2nd driest since 1895. With an average of 1.04 inches (26.42 mm), the region received only 27 percent of normal precipitation. The record driest November was 1917 when the Northeast received only 0.88 inch (22.35 mm) of precipitation. All states were drier than average. Departures ranged from 16 percent of normal in Connecticut, their 2nd driest November, to 37 percent of normal in New Jersey, their 11th driest. The Northeast was slightly drier than average for autumn with 11.36 inches (288.54 mm) of precipitation (98 percent of normal). The region was split down the middle with half of the states drier and half the states wetter than normal. The USDM issued November 27 indicated abnormal dryness continued in upstate New York while a new area of abnormal dryness popped up near the Vermont-New Hampshire border and in central/southern West Virginia.

As summarized by the Western Regional Climate Center, while most of the conterminous United States remained drier than normal this month, several systems delivered above-average precipitation to portions of the Northwest. Over the last few days of November, a series of atmospheric rivers (narrow filaments of high water vapor transport with subtropical origins) brought heavy precipitation to northern and central California as well as parts of Oregon and Idaho. Throughout the West, average monthly temperatures remained above normal with many locations reporting a positive anomaly of at least 3.0 F (1.6 C).

Dry and warm conditions prevailed for much of the Southwest this month. Phoenix, Arizona saw its second warmest November on record at an average 68.4 F (20.2 C). Records at Phoenix began in 1895. In Colorado, Denver airport received only 1.7 in (43 mm) of snowfall this month, 20 percent of its normal 8.7 in (223 mm). In the Great Basin, Las Vegas, Nevada recorded its 3rd warmest November at 60.1 F (15.6 C) in a record dating back to 1937 and Ely, Nevada logged its 4th warmest November at 39.8 F (4.3 C), 6.1 F (3.4 C) above normal. Tonopah, Nevada tied 1995 for warmest autumn on record with a September-October-November average of 56.0 F (13.3 C). Records in Tonopah began in 1902. Throughout New Mexico, year-to-date average temperatures have been some of the highest on record. The January-November average temperature in Albuquerque was 62.0 F (16.7 C), the warmest such period in a record beginning in 1914. Roswell and Clayton also saw near-record year to date average temperatures. In addition, Clayton experienced its driest January-November period, receiving only 7.4 in (188 mm) so far this year and no precipitation this month. Normal January-November precipitation at Clayton is 15.43 in (392 mm) and records began in 1896.

The Northwest was dominated by wet and warm conditions. Between November 28-30, 3-day precipitation totals farther south at windward locations in California's Coast Range between Big Sur and the San Francisco Bay Area were over 6 in (152 mm). This event brought monthly totals to over 200 percent of normal at some locations. Farther inland, some of the highest 3-day totals in the southern Cascades and northern Sierra Nevada were over 8 in (203 mm). Several long-standing daily precipitation records were surpassed in northern California and Oregon. Seattle, Washington recorded its 4th wettest November on record with a total of 9.17 in (233 mm) and also its 9th warmest at an average 47.4 F (8.6 C) for the month. Several other western Washington locations also recorded top 10 warmest November temperatures. Above-normal monthly precipitation totals were also observed throughout Montana, providing relief from persistent dry conditions this year. For the year-to-date, 2012 was the warmest on record at Billings with an average 53.3 F (11.8 C) and also the driest at a total 6.86 in (174 mm). Records at Billings began in 1934. Miles City, Montana and Sheridan, Wyoming also experienced top 10 warmest and driest conditions year-to-date on record.

Dry conditions persisted in Hawaii. Following its driest October in a record beginning in 1950, Lihue, Kauai received only 0.58 in (14.7 mm) this month and tied 1968 for the driest November on record. Stations throughout the state recorded below normal precipitation, with percentages of normal as low as 9 percent in Honolulu. At the end of November, the USDM classified 54 percent of the state as experiencing some level of drought and the rest of the state abnormally dry.

Upper Colorado River Basin: As reported by the Colorado Climate Center, the December 4th NIDIS (National Integrated Drought Information System) assessment for the Upper Colorado River Basin (UCRB) indicated that, for the month of November, most of the UCRB received below average precipitation. The Wasatch and Uintah ranges in Utah received between 2 and 3 inches for the month, while much of the higher elevations of western Colorado and southwest Wyoming received between 0.5 and 1.5 inches. This is below normal for this time of year though and most of the basin saw between 10 percent and 50 percent of average precipitation. East of the basin, the rest of Colorado was very dry, with most of eastern Colorado receiving less than 0.5 inch for the month and between 0 percent and 25 percent of the normal moisture received for November. Accumulated snowpack was much less than average on the east side of the UCRB and slightly below average on the west side of the basin. Sub-basins in western Colorado and along the Colorado River valley in eastern Utah are all between 15 percent and 45 percent of average snowpack. Northeast Utah and southwest Wyoming basins are around 80 percent to 100 percent of average snowpack. For the month of November, all of the UCRB saw warmer than average temperatures. With warmer than average temperatures, there is a risk that the snowpack that has built up could possibly melt back down.

As of December 2nd, about 27 percent of the USGS streamgages in the UCRB recorded normal (25th to 75th percentile) to above normal 7-day average streamflows. About 45 percent 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 concentrated around the Colorado River headwaters in Colorado and along the lower San Juan River. The best conditions (near normal) are concentrated around the Upper Green River. Many of the gages are under frozen conditions and the number of reporting sites has decreased from 130 gages one month ago to 73 gages.

The VIC soil moisture model shows dry soils through most of Wyoming, with soil dryness below the 20th percentile in northeast Utah and northwest Colorado. When modeled soil moisture is combined with snowpack, northwest Colorado shows dryness below the 5th percentile, while northeast Utah shows dryness below the 10th percentile. Dry soils also show up in southeast Colorado with near normal soil moisture in north-central Colorado and in the San Luis Valley in southern Colorado. Last month, many of the major reservoirs in the UCRB saw smaller volume decreases than what is normal for this time of year, with Flaming Gorge staying near steady and Lake Granby seeing a slight increase. Dillon, Lake Powell, and McPhee saw larger decreases than what is normal for this time of year. Most of the reservoirs are between 60 percent and 80 percent of their early December averages and around 60 percent to 80 percent of last year's volumes.

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, in October and November, record low precipitation totals occurred at several locations in the state. Fortunately for Kauai, the first week of December produced 2 to 4 inches of rainfall which should help bring some drought relief but the rest of the state has thus far remained dry. The drought depiction for Kauai remained unchanged over the past month. This includes extreme drought, or D3 category conditions in the USDM map, over the southeastern portion of the island, and severe drought, or the D2 category, over south Kauai from Koloa to Waimea. It is too soon to tell how much improvement the recent rains will bring though it is estimated to be about one D-category worth of change. Extreme drought also remains in place over the southwest slopes of Lanai, western Molokai and southwest Maui from Kihei to Makena. Big Island extreme drought continues to cover 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 persists in Maui county on central and northeastern areas of 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. Moderate drought, or the D1 category, expanded into the south Hilo and Puna districts in recent weeks.

Some drought impacts impacts in Hawaii include the following:

KAUAI.
NO SIGNIFICANT CHANGES SINCE THE NOVEMBER 8 UPDATE.  PASTURES NEAR
KOLOA AND MAHAULEPU IN THE SOUTHEASTERN PORTION OF THE ISLAND HAVE
ALREADY BEEN DESTOCKED.  CATTLE WEIGHTS HAVE ALSO BEEN SIGNIFICANTLY
REDUCED DUE TO POOR PASTURE CONDITIONS.

OAHU.
NO SIGNIFICANT CHANGES SINCE THE NOVEMBER 8 UPDATE.  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 NOVEMBER 8 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 NOVEMBER 8 UPDATE.  THE MIDDLE AND
LOWER ELEVATIONS OF THE ISLAND...ESPECIALLY ALONG THE NORTH-...EAST-
AND SOUTH-FACING SLOPES...REMAIN VERY DRY AND 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.
RECENT RAINFALL OVER SOUTH MAUI NEAR ULUPALAKUA AND KEPUNI HELPED
IMPROVE DROUGHT CONDITIONS BUT ONLY IN SMALL AREAS DUE TO THE HIGHLY
LOCALIZED NATURE OF THE SHOWERS.  THERE HAVE BEEN NO ADDITIONAL
IMPACTS RECENTLY BECAUSE THE PASTURES IN THE WORST DROUGHT AREAS
HAVE ALREADY BEEN DESTOCKED.  PRODUCTION AT THE OLINDA WATER
TREATMENT FACILITY REMAINED BELOW NORMAL DUE TO A LOW WATER SUPPLY.
THE MAUI COUNTY DEPARTMENT OF WATER SUPPLY CONTINUED ITS LONG
STANDING REQUEST 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 RESIDENTS ALSO REMAINED IN
EFFECT.

BIG ISLAND.
BELOW NORMAL RAINFALL HAS FORCED SOME FARMERS TO HAUL WATER IN THE
NORMALLY WET PUNA DISTRICT.  ALTHOUGH RAINFALL IS ALSO BELOW NORMAL
ALONG THE LOWER NORTHEASTERN SLOPES...RECENT REPORTS INDICATE THAT
THERE APPEARS TO BE SUFFICIENT RAINFALL TO MEET NEEDS AND THAT
VEGETATION IN MOST AREAS IS STILL GREEN.  CONDITIONS REMAIN VERY
POOR FOR PASTURES AND NON-IRRIGATED AGRICULTURE IN MOST OF THE KAU
AND LEEWARD KOHALA SECTIONS OF THE ISLAND.

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), November was drier than normal for Guam and Koror, and much drier than normal for Kwajalein and Saipan. November rainfall amounts at Guam, Kwajalein, and Saipan were below six inches. Kwajalein has been well below normal for the last three months and Koror has been below normal for the last two months. Total rainfall for the last 12 months (December 2011-November 2012) was above normal for all stations except Koror, Kwajalein, Majuro, and Pohnpei.


X
  • Percent of Normal Precip
  • Precipitation
  • Normals
Pacific Island Percent of 1981-2010 Normal Median Precipitation
Station NameDec
2011
Jan
2012
Feb
2012
Mar
2012
Apr
2012
May
2012
Jun
2012
Jul
2012
Aug
2012
Sep
2012
Oct
2012
Nov
2012
Dec 2011-
Nov 2012
Chuuk125%57%181%107%40%173%131%141%169%86%128%144%117%
Guam NAS103%162%94%215%121%224%107%66%179%126%92%74%102%
Kapingamarangi124%109%71%121%102%143%179%146%192%147%138%167%121%
Koror97%36%126%121%120%122%95%88%102%111%78%67%88%
Kosrae174%65%185%60%84%86%99%124%144%109%113%119%94%
Kwajalein84%134%114%84%68%161%117%120%95%57%73%45%86%
Lukonor251%86%124%135%76%106%125%82%73%148%74%178%104%
Majuro91%107%65%194%97%59%81%68%87%67%46%154%89%
Pago Pago75%61%98%131%90%126%115%105%59%195%54%181%92%
Pohnpei110%82%138%98%45%115%100%92%96%90%82%109%92%
Saipan110%77%183%35%33%166%118%77%135%101%172%31%108%
Yap116%33%117%185%89%142%99%84%128%187%140%121%116%
Pacific Island Precipitation (Inches)
Station NameDec
2011
Jan
2012
Feb
2012
Mar
2012
Apr
2012
May
2012
Jun
2012
Jul
2012
Aug
2012
Sep
2012
Oct
2012
Nov
2012
Dec 2011-
Nov 2012
Chuuk14.015.7413.138.875.0219.5615.2716.9221.7810.0414.6815.30160.32
Guam NAS5.246.502.854.453.057.636.636.7426.4215.9810.565.45101.5
Kapingamarangi12.199.946.6113.8213.9117.2424.6820.6515.5714.5611.3215.44175.93
Koror10.793.6510.819.038.7914.4916.5416.3613.7213.019.237.68134.1
Kosrae28.1110.8923.939.5914.7015.3514.5618.5520.4615.5212.3316.49200.48
Kwajalein5.594.223.011.973.5810.828.0811.839.236.178.185.0977.77
Lukonor28.347.2211.0612.518.6012.3514.5313.0810.2615.028.3916.18157.54
Majuro10.378.274.4612.759.145.968.897.5410.157.475.8420.69111.53
Pago Pago9.698.1411.7614.008.4112.156.135.843.1912.734.9918.34115.37
Pohnpei17.6110.7513.1712.928.3122.9814.8614.2113.6211.2712.5916.18168.47
Saipan4.231.964.750.660.883.964.266.8617.7310.2418.311.7575.59
Yap9.912.116.098.435.0011.1411.9512.7418.9225.1917.0810.67139.23
Pacific Island 1981-2010 Normal Median Precipitation (Inches)
Station NameDec
2011
Jan
2012
Feb
2012
Mar
2012
Apr
2012
May
2012
Jun
2012
Jul
2012
Aug
2012
Sep
2012
Oct
2012
Nov
2012
Dec 2011-
Nov 2012
Chuuk11.2510.107.258.3212.4711.3011.6611.9812.8611.7111.5110.61136.77
Guam NAS5.114.013.032.072.533.406.1810.1414.7412.6611.447.3899.09
Kapingamarangi9.849.159.2711.4313.6412.0813.7814.158.139.938.199.27145.85
Koror11.1610.188.567.447.3211.8317.4818.5313.5011.7711.8411.39152.90
Kosrae16.1116.6712.9316.0617.5117.7514.6414.9114.2214.2210.9413.83213.87
Kwajalein6.663.162.642.355.266.726.939.879.7410.7411.1811.2890.41
Lukonor11.278.418.939.2611.3111.6911.6515.9314.0410.1511.329.08151.36
Majuro11.397.746.886.589.4210.1111.0111.1711.6911.1712.7313.44125.25
Pago Pago12.8413.3412.0010.689.399.665.335.555.386.539.2610.14125.57
Pohnpei16.0813.189.5513.1718.4119.9614.8115.4314.2612.5515.2714.83182.36
Saipan3.852.532.591.892.632.383.628.9113.1310.0910.625.6170.25
Yap8.516.395.194.565.637.8512.0415.0814.8213.5012.188.83120.31

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 (47 years).

The Northern Hemisphere snow cover extent during November 2012 was above-average, ranking as the fifth largest on record for the month, and marked the fourth consecutive November with above-average snow cover for the hemisphere. The Northern Hemisphere snow cover extent was 36.0 million square km (13.9 million square miles), 2.3 million square km (889,000 square miles) above average. The autumn season (September-November) snow cover extent was above average, and ranked as the 10th largest (37th smallest) in the 47-year period of record.

During November, the North American snow cover extent was above average and ranked as the 12th largest on record. The monthly snow cover extent was 13.9 million square km (5.4 million square km), 590,000 square km (227,800 square miles) above average. This was the third consecutive November with above-average snow cover extent for the continent and the largest since November 2003. Several large storms hit the west coast of North America during the month, with above-average snow cover occurring across the Canadian Rockies and Prairies and extending into the north-central United States. Below-average snow cover was observed across the U.S. Rockies, Central Plains, Midwest, and Northeast and eastern Canada. For the autumn season, North American snow cover was above average and ranked as the 15th largest (32nd largest) seasonal snow cover extent for the continent. For more information on the U.S. November 2012 snow events, please visit the U.S. November Snow/Ice Summary page.

Eurasian snow cover was above average in November and ranked as the eighth largest on record at 22.0 million square km (8.5 million square miles), 1.7 million square km (656,000 square miles) above average. Much of Russia, Mongolia, and eastern China experienced above-average snow cover during November, while southeastern Russia, Turkey, and the Tibetan Plateau had below-average snow cover. The autumn snow cover extent was also above average and ranked as the 12th largest (35th smallest) on record for the continent.

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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 November 2012 was 9.93 million square km (3.83 million square miles). The monthly sea ice extent was 12.19 percent below average and the third smallest November Arctic sea ice extent in the satellite record. Only the November sea ice extents in 2006 and 2010 were smaller. This was the 19th consecutive November and 138th consecutive month with below-average Arctic sea ice extent. November Arctic sea ice extent has decreased at an average rate of 4.8 percent per decade.

Arctic sea ice expanded rapidly during November, at a rate of 98,600 square km (38,100 square miles) per day which is faster than average for the month. By the end of the month, the central Arctic Ocean had completely refrozen and the Bering Sea had above-average sea ice coverage. The Barents and Kara seas were much slower to freeze, both of which continued to be mostly ice free by the end of November. Below-average ice cover was observed for Baffin and Hudson Bays.

The November 2012 Southern Hemisphere sea ice extent was 16.62 million square km (6.42 million square miles), 2.36 percent above average and the sixth largest November sea ice extent in the 1979-2012 period of record. Antarctic sea ice extent during November has increased at an average rate of 0.7 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

November Lower Troposphere
November Anomaly Rank
(out of 34 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH +0.28 +0.50 Coolest 32nd 1984 -0.53 -0.95 +0.16 +0.29
Warmest 3rd 2009 +0.41 +0.74
RSS +0.10 +0.18 Coolest 22nd 1984 -0.37 -0.67 +0.12 +0.21
Warmest 11th 2003 +0.26 +0.47
Ties: 2006, 1998
September-November Lower Troposphere
September–
November
Anomaly Rank
(out of 34 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH +0.32 +0.58 Coolest 32nd 1984 -0.48 -0.86 +0.17 +0.31
Warmest 3rd 2009 +0.37 +0.67
RSS +0.19 +0.34 Coolest 28th 1984 -0.39 -0.70 +0.14 +0.26
Warmest 6th 1998 +0.28 +0.50
Ties: 2001
Year-to-Date Lower Troposphere
January–
November
Anomaly Rank
(out of 34 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH +0.16 +0.29 Coolest 26th 1984 -0.34 -0.61 +0.14 +0.25
Warmest 9th 1998 +0.44 +0.79
RSS +0.10 +0.18 Coolest 24th 1985 -0.37 -0.67 +0.13 +0.24
Warmest 11th 1998 +0.47 +0.85

Mid-troposphere

November Mid-troposphere
November Anomaly Rank
(out of 34 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH +0.12 +0.22 Coolest 28th 1984 -0.27 -0.49 +0.04 +0.07
Warmest 5th 2009 +0.24 +0.43
Ties: 2003, 2001
RSS +0.15 +0.27 Coolest 28th 1985 -0.29 -0.52 +0.06 +0.11
Warmest 7th 2009, 2002 +0.24 +0.43
UW-UAH +0.16 +0.29 Coolest 27th 1984 -0.40 -0.72 +0.12 +0.21
Warmest 8th 2009 +0.33 +0.59
UW-RSS +0.19 +0.34 Coolest 28th 1985, 1984 -0.31 -0.56 +0.12 +0.22
Warmest 7th 2009 +0.30 +0.54
September-November Mid-troposphere
September–
November
Anomaly Rank
(out of 34 years*)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH +0.18 +0.32 Coolest 30th 1984 -0.33 -0.59 +0.08 +0.14
Warmest 5th 1998 +0.24 +0.43
RSS +0.21 +0.38 Coolest 29th 1985 -0.34 -0.61 +0.10 +0.18
Warmest 4th 1998 +0.26 +0.47
Ties: 2005, 2002
UW-UAH +0.23 +0.41 Coolest 30th 1984 -0.44 -0.79 +0.15 +0.27
Warmest 5th 1998 +0.35 +0.63
UW-RSS +0.26 +0.47 Coolest 30th 1984 -0.38 -0.68 +0.16 +0.28
Warmest 5th 1998 +0.34 +0.61
RATPAC* +0.40 +0.72 Coolest 54th 1964 -0.86 -1.55 +0.16 +0.29
Warmest 2nd 2006 +0.45 +0.81

*RATPAC rank is based on 55 years of data

Year-to-Date Mid-troposphere
January–
November
Anomaly Rank
(out of 34 years*)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH +0.01 +0.02 Coolest 18th 1984 -0.24 -0.43 +0.05 +0.09
Warmest 16th 1998 +0.45 +0.81
Ties: 1981
RSS +0.06 +0.11 Coolest 22nd 1985 -0.29 -0.52 +0.08 +0.15
Warmest 13th 1998 +0.46 +0.83
UW-UAH +0.06 +0.11 Coolest 23rd 1984 -0.32 -0.58 +0.11 +0.19
Warmest 11th 1998 +0.55 +0.99
Ties: 1980
UW-RSS +0.12 +0.22 Coolest 24th 1985, 1984 -0.32 -0.58 +0.14 +0.25
Warmest 10th 1998 +0.54 +0.97
Ties: 2004
RATPAC* +0.19 +0.34 Coolest 47th 1965 -0.79 -1.42 +0.15 +0.27
Warmest 9th 2010 +0.51 +0.92

*RATPAC rank is based on 55 years of data

Stratosphere

November Stratosphere
November Anomaly Rank
(out of 34 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH -0.35 -0.63 Coolest 12th 2000 -0.70 -1.26 -0.44 -0.79
Warmest 22nd 1982 +1.50 +2.70
Ties: 1999
RSS -0.34 -0.61 Coolest 8th 2000 -0.66 -1.19 -0.35 -0.63
Warmest 27th 1982 +1.36 +2.45
September-November Stratosphere
September–
November
Anomaly Rank
(out of 34 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH -0.36 -0.65 Coolest 12th 2000 -0.65 -1.17 -0.43 -0.77
Warmest 23rd 1991 +1.52 +2.74
RSS -0.34 -0.61 Coolest 8th 2000 -0.56 -1.01 -0.33 -0.59
Warmest 26th 1991 +1.47 +2.65
Ties: 2003
Year-to-Date Stratosphere
January–
November
Anomaly Rank
(out of 34 years)
Record Years Decadal Trend
°C °F Year °C °F °C °F
UAH -0.42 -0.76 Coolest 3rd 2008 -0.48 -0.86 -0.37 -0.67
Warmest 32nd 1982 +1.01 +1.82
RSS -0.41 -0.74 Coolest 1st 2012 -0.41 -0.74 -0.30 -0.53
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: 5 December 2012


Overview

During November, the year-to-date pattern for incidents of fewer fires with larger size continued. The year-to-date total of 55,505 fires was the least since records began in 2000 for any January through November period. Whereas, the year-to-date average fire size was the most since 2000 for any January through November period, with the year-to-date total acreage burned being the 2nd highest since 2000. The monthly total number of 3,694 fires was the 5th most for November in the thirteen-year record. November's average fire size and monthly total acres burned both ranked at the median value (7th highest and 7th lowest) for any November in the 2000-2012 record. The monthly average fire size reached 41.3 acres per fire, which was well below the 10-year average (based on 2001-2010) of 71.4 acres per fire. The January through November average fire size was 165.0 acres. Over 150,000 acres burned by wildfires in November, with a total of 9.1 million acres having burned since January 2012.

1-Month Wildfire Statistics*
November Totals Rank
(out of 13 years)
Record 2000-2010
Average
Value Year
Acres Burned 152,697 7ᵗʰ Most 478,648 2003 191,797
7ᵗʰ Least
Number of Fires 3,694 5ᵗʰ Most 10,223 2001 3,590
9ᵗʰ Least
Acres Burned per Fire 41.3 7ᵗʰ Most 227.5 2003 72.1
7ᵗʰ Least
3-Month Wildfire Statistics*
September–November Totals Rank
(out of 13 years)
Record 2000-2010
Average
Value Year
Acres Burned 1,431,323 4ᵗʰ Most 1,992,436 2007 1,038,936
10ᵗʰ Least
Number of Fires 10,981 10ᵗʰ Most 22,843 2001 14,667
4ᵗʰ Least
Acres Burned per Fire 130.3 3ʳᵈ Most 176.0 2006 78.6
11ᵗʰ Least
Year-to-Date Wildfire Statistics*
January–November Totals Rank
(out of 13 years)
Record 2000-2010
Average
Value Year
Acres Burned 9,156,278 2ⁿᵈ Most 9,508,251 2006 6,434,326
12ᵗʰ Least
Number of Fires 55,505 13ᵗʰ Most 91,094 2000 73,841
Least on Record
Acres Burned per Fire 165.0 Most on Record 165.0 2012 87.7
13ᵗʰ Least

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

Discussion

As exceptional drought remained anchored over the central Great Plains, dryness expanded into central North Carolina and Virginia from a second location of exceptional drought centered over Georgia during November. In early November, the moisture deficits mounted across Georgia and South Carolina (Keetch-Byram Drought Index values exceeded 500 units), before mid-month showers brought brief improvement. Dryness spread from western and central Kentucky to dip across northeastern Tennessee by the end of the month, where an outbreak of wildfire incidents resulted. Drought conditions intensified in eastern Oklahoma, and northern and southeastern Texas. Severe drought expanded in southwestern Nevada and southeastern California in the latter half of November. Although the east-facing slopes of the Hawaiian islands received precipitation from mid-month onward, the western areas continued to experience drought.

Significant Events


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


California

Precipitation across southern California remained below-normal during November. The ongoing dryness in wind-prone areas provided conditions for significant fire potential. Multiple wildfires burned during the month. The Devore Fire ignited on November 5th in the chaparral along Interstate 15, which resulted in the day-long closure of the highway through Cajon Pass. Santa Ana winds fanned the blaze quickly through more than 330 acres in the foothills of the San Bernardino Mountains. Three residences near the Mathews Ranch were evacuated, but no damage was reported. Over 450 firefighters with the support of 10 aircraft contained the wildfire on November 6th. The following week the Cut Fire sparked in the same area, but was contained after charring about 4 acres on November 11th. The wildfire also forced a brief closure of one northbound lane of Interstate 15 for a few hours. Off-shore winds, which strengthened unexpectedly, drove a prescribed 430-acre burn in Montana de Oro State Park outside of containment to become a wildfire on November 13th. The Creek Fire burned an additional 100 acres of brush and hardwoods before being controlled on November 15th. The Ranch Fire, which ignited on November 25th to the northeast of San Bernardino near Apple Valley, caused the evacuation of the Horse Springs Campground. The wildfire was contained the next day after scorching 10 acres of grass and chaparral.

Hawaii

Westward portions of several Hawaiian islands had above-normal significant fire potential during November. A couple of wildfires developed on Oahu's southern coast at mid-month where dry conditions and uncontrolled vegetation provided fuel, according to media reports. A wildfire at Ewa Beach burned about 100 acres and threatened residences on November 10th. Firefighting efforts were hampered due to the lack of fire hydrants. Another wildfire sparked the same day near Kalaeloa, which burned about 35 acres of dry brush without posing a threat to homes.

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).

Early in the month, only a few large wildfires formed and their locations coincided with the low 10-hour fuel moistures (at or below 10 percent) in southeastern Kentucky, southeastern Oregon, and southern California. In Kentucky, the Cave Branch Fire consumed over 200 acres. In Oregon, the Juniper Creek Fire consumed 1,500 acres of brush and grass. Critically low 10-hour fuel moistures (under 5 percent) spanned the Four Corners area of the southwest United States. Moreover, the lower half of the country experienced 10-hour fuel moistures at or below 8 percent. Both the 100-hour and 1000-hour fuel moistures were at or below 10 percent from Nevada to New Mexico, with most areas west of the High Plains at or below 15 percent, except for the Pacific Northwest and northern California.


Fuel moistures generally improved at all intervals (10-hour, 100-hour, and 1000-hour) from precipitation received during the second and third weeks of November, except in the Northeast. At mid-month, only southern Arizona and southern New Mexico's fuel moistures remained below 5 percent for the 10-hour interval. As 10-hour fuel moistures dropped across the middle and northern Atlantic states, an increase in wildfire activity occurred in the southern Appalachian Mountains. Wildfires erupted in North Carolina, northeastern Tennessee, southeastern Kentucky, and western Virginia. Pilot Mountain Fire in North Carolina, which began as a prescribed 200-acre burn to clear dead wood and underbrush, tripled in size on November 8th when strong winds spread the blaze along the Jomeokee Trail. The fire's low intensity spared standing trees, but forced closure of the Pilot Mountain State Park where other than for some burned fences at viewing areas no structural losses occurred, according to media reports. The fire was contained at 675 acres and the park reopened on November 21st. The Spade wildfire burned over 800 acres in Virginia's Jefferson National Forest (northwest of Roanoke) and threatened homes from November 13th-15th. Another Virginia wildfire, the 3 Fingers Fire, burned about 100 acres from November 10th-15th.


During the latter part of November, the 10-hour and 100-hour fuel moistures remained at or below 15 percent in the Piedmont plateau regions of the eastern U.S. (parts of central Virginia, western and central North Carolina, upstate South Carolina, and northeast Georgia). In northern Georgia, a wildfire in the Chattahoochee-Oconee National Forest burned over 200 acres. The blaze, which sparked on November 25th, forced a temporary closure to the Appalachian Trail. In North Carolina, the High Eagle fire burned over 150 acres in the rugged terrain of Caldwell County near Lenoir before being contained on November 28th, according to media reports. Large wildfires continued to develop in eastern Tennessee, Kentucky and northern Arkansas. The Stone Mountain Fire consumed over 2,000 acres of beetle-killed pines in steep terrain of east Tennessee, while fanned by a northeasterly wind. The blaze burned west of Rogersville from November 15th-24th where it had threatened homes and structures in Hawkins County, according to media reports. Multiple wildfires sparked across eastern Kentucky in late November. The Turkey wildfire burned nearly 600 acres in the Daniel Boone National Forest from November 22nd-27th. The Belles Fork Fire burned nearly 250 acres. The Lime Kiln Fire burned nearly 170 acres from November 18th-20th. The Meathouse Fire burned up to 150 acres. Northwestern Arkansas remained under a moderate fire risk following a summer of hot temperatures and drought conditions, which dried the soil and fine fuels. The Snowball Fire consumed over 300 acres by November 23rd. Gusty winds, fallen leaves, warm temperatures, and low humidity at the end of November combined to keep the fire danger elevated in northwestern Arkansas and eastern Oklahoma.

Did You Know?

Reforestation of Bastrop Lost Pines

In central Texas, preparations for the first volunteer planting workday at the Bastrop State Park occurred during November, according to media reports. Most of the 6,600-acre park's signature "Lost Pines" were destroyed during the 2011 fires — deemed as the most destructive wildfires in the state's history after devastating more than 32,000 acres. Drought-hardy loblolly pine seedlings were nurtured during the past year from over 1,000 pounds of surplus seeds in refrigerated storage. Over 400,000 seedlings were delivered to the park for the planting event commencing on December 1st. The seeds were collected as part of cooperative efforts between five states and eight industrial partners — led by the Texas A&M Forest Service — to promote the best genetic quality seed for use in forest regeneration programs in the Western Gulf Region of the United States. Planting of more than one million seedlings is planned for each of the two next years. Geneticists estimated that the 10-inch tall seedlings need up to 25 years to reach the mature size of the former Bastrop Lost Pines.

More about climate monitoring…


All Fire Related Maps


Citing This Report

NOAA National Climatic Data Center, State of the Climate for November 2012, published online December 2012, retrieved on October 25, 2014 from http://www.ncdc.noaa.gov/sotc/2012/11.