National Climate Report - November 2017
Maps and Graphics
Temperature and Precipitation Ranks
U.S. Percentage Areas
Supplemental November 2017 Information
- Historically Extreme Winter Temperature and Precipitation Maps
- Year-to-date temperature evolution for select U.S. cities
- Year-to-date precipitation evolution for select U.S. cities
- Year-to-date records and near-records
- Climate Highlights — November
November Average Temperature Departures
November Percent of Average Precipitation
- The November nationally averaged temperature was 45.1°F, 3.4°F above the 20th century average, and ranked as the seventh warmest on record.
- Much-above-average temperatures stretched from the California Coast into the Southwest, Central Rockies and Southern Plains. Arizona, Colorado, New Mexico and Utah each had their warmest November on record. The Arizona statewide average temperature of 57.7°F surpassed the previous record set in 2007 by 2.4°F. Near-average temperatures were observed across much of the northern U.S. and along much of the East Coast.
- Much-above-average temperatures were observed along the western and northern coasts of Alaska where Arctic sea ice extent offshore was record and near-record low for the month. Barrow had its warmest November on record with a temperature of 17.2°F, 16.4°F above the 1981-2010 normal, and 1.9°F warmer than the previous record in 1950.
- The contiguous U.S. average maximum (daytime) temperature during November was 56.2°F, 3.5°F above the 20th century average, ranking as the 10th warmest on record. Much-above-average maximum temperatures were observed in the Southwest and Southern Plains. Arizona and New Mexico each had record warm maximum temperatures.
- The contiguous U.S. average minimum (nighttime) temperature during November was 33.9°F, 3.4°F above the 20th century average, ranking as the 11th warmest on record. Much-above-average minimum temperatures were observed in the Southwest, Central Rockies and Southern Plains. Arizona, Colorado, New Mexico and Utah each had record warm maximum temperatures. Near- and below-average minimum temperatures were observed in the Northeast.
- During November there were 7,319 record warm daily high (3,728) and low (3,591) temperature records, which was more than four times the 1,676 record cold daily high (931) and low (745) temperature records.
- Based on NOAA's Residential Energy Demand Temperature Index (REDTI), the contiguous U.S. temperature-related energy demand during November was 32 percent below average and ranked as the 23rd lowest value in the 123-year period of record.
- The national precipitation total was 1.58 inches, 0.65 inch below average, marking the 19th driest November on record.
- Below-average precipitation accumulated for most locations from the Southwest into the Great Plains, Southeast and along the East Coast. Record low precipitation totals were reported in parts of the Southwest and Deep South, with five states having the tenth driest, or drier, November on record. Mississippi ranked third driest, Alabama and Arkansas fourth driest, Oklahoma fifth driest, and Louisiana tenth driest. Little Rock, Arkansas, had its driest November on record with only 0.41 inch of rainfall.
- Above-average precipitation was observed in the Northwest, Northern Rockies and parts of the Midwest. Ohio had its ninth wettest November on record.
- According to the November 28 U.S. Drought Monitor report, 21.1 percent of the contiguous U.S. was in drought, up nearly 9.2 percent compared to the end of October. Drought developed, expanded and intensified in the Southwest, Southern Plains, Lower Mississippi Valley and Southeast. Drought improved in the Northwest, Northern Rockies and parts of the Midwest. Drought also improved for much of Hawaii.
- According to NOAA data analyzed by the Rutgers Global Snow Lab, the monthly snow cover extent across the contiguous U.S. was 440,000 square miles, about 31,300 square miles below the 1981-2010 average. This was the 22nd smallest November snow cover extent in the 52-year period of record.
- Climate Highlights — autumn (September-November)
Sep-Nov Average Temperature Departures
Sep-Nov Percent of Average Precipitation
- The autumn (September-November) temperature was 55.7°F, 2.1°F above the 20th century average, and the 10th warmest on record.
- Above-average temperatures spanned most of the nation during autumn, with the exception of the Northern Rockies and northern High Plains. Record warmth was observed in the Southwest and New England, where Arizona, New Mexico, Connecticut, Maine, Massachusetts and New Hampshire were each record warm. The record autumn warmth in the Southwest was driven largely by warm November temperatures, while the record warmth in New England was mostly due to warm October temperatures.
- The contiguous U.S. average maximum (daytime) temperature during September-November was 67.8°F, 2.0°F above the 20th century average, tying 1954 as the 14th warmest on record. Much-above-average maximum temperatures were observed in the Southwest and Northeast. Arizona, New Mexico, Maine, New Hampshire, and Rhode Island each had record warm autumn maximum temperatures.
- The contiguous U.S. average minimum (nighttime) temperature during September-November was 43.5°F, 2.2°F above the 20th century average, ranking as the seventh warmest on record. Much-above-average minimum temperatures spanned the Southwest, parts of the Great Plains, Southeast, Great Lakes, and Northeast. Arizona had a record warm autumn minimum temperature.
- Based on REDTI, the contiguous U.S. temperature-related energy demand during September-November was 66 percent below average and ranked as the fifth lowest value in the 123-year period of record.
- The autumn precipitation total was 6.43 inches, 0.45 inch below average, and ranked in the driest third of the historical record.
- Below-average precipitation was observed for parts of the Southwest, Southern Plains, Lower Mississippi Valley and Mid-Atlantic. Parts of the Southwest, including Flagstaff and Phoenix, Arizona, were record dry. Arkansas was also record dry, receiving only 36.1 percent of average rainfall statewide. Little Rock, Arkansas, received just 2.24 inches of precipitation during the season, dipping below the previous record of 2.90 inches set in 1904.
- Above-average precipitation was observed in the Northwest, Northern Rockies, and parts of the Plains, Midwest, Southeast and Northeast.
- Climate Highlights — year-to-date (January-November)
Jan-Nov Average Temperature Departures
Jan-Nov Percent of Average Precipitation
- The year-to-date U.S. average temperature was the third warmest on record at 56.4°F, 2.6°F above average. Only January-November of 2012 and 2016 were warmer.
- Above-average temperatures spanned the nation during the year-to-date. Two states in the Southwest – Arizona and New Mexico – and six states in the East – Florida, Georgia, North Carolina, South Carolina, Virginia and West Virginia – were record warm for the first 11 months of the year.
- The contiguous U.S. average maximum (daytime) temperature during January-November was 68.3°F, 2.4°F above the 20th century average, the fourth warmest on record. Much-above-average temperatures were observed in the Southwest, Southern Plains, and most of the East. Arizona had a record warm year-to-date maximum temperature.
- The contiguous U.S. average minimum (nighttime) temperature during January-November was 44.5°F, 2.9°F above the 20th century average, ranking as the second warmest on record. Only the year-to-date minimum temperature in 2016 was warmer. Much-above-average minimum temperatures spanned most of the nation with 14 states across the South and Mid-Atlantic record warm.
- Based on REDTI, the contiguous U.S. temperature-related energy demand during January-November was record low in the 123-year period of record.
- The year-to-date precipitation total for the nation was 30.60 inches, 3.01 inches above normal, and the ninth wettest on record.
- Many locations had a wetter-than-average year-to-date with much-above-average precipitation totals across the West and the Great Lakes. Michigan had its wettest January-November on record with 37.31 inches of precipitation, 8.19 inches above average. This bested the previous record of 37.04 inches set in 1985.
- Parts of the northern Plains were drier than normal for the year-to-date. North Dakota had the eighth driest January-November, resulting in large part from the significant drought there earlier this year.
- The U.S. Climate Extremes Index (USCEI) for the year-to-date was the third highest value on record at more than double the average. On the national scale, extremes in warm maximum and minimum temperatures, one-day precipitation totals, days with precipitation and landfalling tropical cyclones contributed to the elevated USCEI. The USCEI is an index that tracks extremes (falling in the upper or lower 10 percent of the record) in temperature, precipitation, drought and landfalling tropical cyclones across the contiguous U.S.
- The CEI ranked among the ten highest values on record for the Northeast, Ohio Valley, Upper Midwest, Southeast, South, Southwest and West. In each of these regions extremes in warm maximum and minimum temperature were above average. In the Northeast, days with precipitation ranked as the fifth highest. In the Upper Midwest, the spatial extent of wetness was record high and days with precipitation was sixth highest. In the South, one-day precipitation totals was the eighth highest. In the West, one-day precipitation totals ranked as the fourth highest.
**A comparison of the national temperature departure from average as calculated by NCDC's operational dataset (nClimDiv), the U.S. Historical Climatology Network (USHCN), and the U.S. Climate Reference Network (USCRN) is available on our National Temperature Index page.**
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 Centers for Environmental Information.
- Northeast Region: (Information provided by the Northeast Regional Climate Center)
- With an average temperature of 38.1 degrees F (3.4 degrees C), November was 1.4 degrees F (0.8 degrees C) colder than normal in the Northeast. State average temperatures ranged from 1.8 degrees F (1.0 degrees C) below normal in New York to normal in Delaware. With its ninth warmest September, second warmest October, and a colder-than-normal November, the Northeast averaged out to have its fifth warmest autumn since 1895. The region's average temperature of 52.4 degrees F (11.3 degrees C) was 2.6 degrees F (1.4 degrees C) above normal. Connecticut, Maine, Massachusetts, and New Hampshire had their warmest autumn since recordkeeping began. This autumn ranked among the 20 warmest on record for the other eight states: Rhode Island and Vermont, second warmest; New Jersey, sixth warmest; Delaware and New York, eighth warmest; Maryland, 10th warmest; Pennsylvania, 14th warmest; and West Virginia, 20th warmest. Average temperatures ranged from 1.4 degrees F (0.8 degrees C) above normal in West Virginia to 3.9 degrees F (2.2 degrees C) above normal in New Hampshire. Four major climate sites had their warmest autumn on record: Burlington, Vermont; Concord, New Hampshire; Islip, New York; and Providence, Rhode Island.
- November was drier than normal in the Northeast, with 2.52 inches (64.01 mm) of precipitation, 66 percent of normal. State precipitation ranged from 36 percent of normal in Connecticut to 78 percent of normal in Pennsylvania. Five states ranked this November among their 20 driest: New Hampshire, 11th driest; Connecticut, 12th driest; Massachusetts, 13th driest; Vermont, 18th driest; and New Jersey, 19th driest. September and November were drier than normal, and October was wetter than normal, so autumn averaged out to be drier than normal. The region received 10.69 inches (271.53 mm) of precipitation, 92 percent of normal. Ten states were drier than normal, with precipitation for all states ranging from 72 percent of normal in Maryland to 103 percent of normal in Maine.
- The U.S. Drought Monitor released on November 2 showed 10 percent of the Northeast was abnormally dry. Dryness eased in western Pennsylvania and the northern Panhandle of West Virginia, where above-normal precipitation fell during the month. Conditions also eased in northeastern Massachusetts, southeastern New Hampshire, and parts of eastern Maine. However, abnormal dryness lingered or expanded where below-normal precipitation fell during November, including the eastern Panhandle of West Virginia, central and southern Maryland, south-central and northeastern Pennsylvania, southeastern New York, northern New Jersey, central Vermont, and parts of coastal Maine. The U.S. Drought Monitor released on November 30 showed 8 percent of the Northeast was abnormally dry.
- November 7 brought an end to Boston, Massachusetts' streak of consecutive days with a temperature above 40 degrees F (4 degrees C) at 201 days, which tied 1968 for the longest streak. Also, a few sites had their first 32 degrees F (0 degrees C) freeze on November 7, including Rochester and Buffalo in New York. Both sites had a frost free season (time between last spring freeze and first fall freeze) lasting 212 days, which was Rochester's second longest frost free season since 1872 (record is 216 days) and Buffalo's fifth longest since 1874. For much of the Northeast, though, the first freeze arrived on November 10 or 11, which was later than usual, in some instances by more than 3 weeks. With a freeze on November 10, Dulles Airport, Virginia, was one day short of tying its record for latest first frost (record is November 11, 2005). It was the first time since 1963 that both Dulles Airport and Washington National, D.C., had their first freeze on the same date. New Brunswick, New Jersey, had a low of 20 degrees F (-7 degrees C) on November 11, which was the site's lowest first freeze temperature since 1896. The previous lowest first freeze temperature was 25 degrees F (-4 degrees C). Caribou, Maine, did not receive measurable snowfall (0.1 inches [0.3 cm]) until November 17, making it the site's fourth latest measurable snow since 1940. The region also experienced severe weather in November. On November 5, an EF-1 tornado damaged buildings and trees in Erie County, Pennsylvania. On the same day, Erie received 2.85 inches (72.39 mm) of precipitation, the site's largest one-day precipitation total for November since 1873. Buffalo, New York, received 2.01 inches (51.05 mm) of rain, which was their fifth greatest one-day precipitation for November since 1871. On November 19, an EF-1 tornado tracked through Allegheny and Westmoreland counties in western Pennsylvania. Data from the National Centers for Environmental Information's Storm Events Database (records to 1950) indicated that it was the first tornado in November and the latest in a calendar year for Allegheny County and only the second November tornado and the second latest in a calendar year for Erie and Westmoreland counties.
- For more information, please go to the Northeast Regional Climate Center Home Page.
- Midwest Region: (Information provided by the Midwest Regional Climate Center)
- November precipitation totals ranged from less than 25 percent of normal in the western parts of the region to more than 200 percent of normal in a large area of Ohio. The totals ranged from less than 0.10 inches (3 mm) near the Iowa-Minnesota-South Dakota border to more than 6.00 inches (152 mm) in northern Ohio. Statewide values ranged from 20 percent of normal for Iowa to 154 percent of normal in Ohio. Missouri ranked as the 11th driest November in its history (since 1895), Iowa 13th driest, Wisconsin 14th driest, and Minnesota 17th driest. On the other end of the scale, Ohio ranked 9th wettest and Indiana ranked 24th wettest. For the fall season (September to November), drier-than-normal conditions stretched from Missouri to Wisconsin while wetter-than-normal conditions in the surrounding areas. There was a lot of variation during the season with states having months ranking among both the driest and the wettest.
- November temperatures were below normal in the upper Midwest and slightly above normal in parts of Missouri. The coolest readings were around Lake Superior where monthly averages were 3 to 4 degrees F (2 C) below normal while parts of Missouri were 1 to 2 degrees (1 C) above normal. Temperatures were generally coolest around the 10th and climbed above average by the last week of the month. For the fall season, temperatures were slightly above normal for much of the region. September and October were warmer than normal and then cooler in November.
- November 5th had an outbreak of severe weather that stretched from the St. Louis, Missouri area to Ohio. There were 21 tornadoes including 17 in Ohio. The annual average number of tornadoes in the state is just 20. One tornado that tracked 39 miles (62 km) from east central Indiana to west central Ohio was responsible for 8 injuries. There were numerous wind reports of 70 to 90 miles per hour (112 to 144 km per hours) and reports that topped 100 miles per hour (160 km per hour) in multiple Ohio locations.
- Drought in November was most prominent in Missouri though small areas of Iowa, Minnesota, and Illinois were also affected. The drought in Missouri did not expand in November but it did intensify. At the beginning of the month, the drought was all classified as moderate drought and by the end of the month, about half of the Missouri drought was classified as severe drought.
- Harvest of corn and soybeans neared an end in November. The corn harvest was behind the 5-year average in parts of the region. Some states were a week or two behind average during much of the fall.
- For further details on the weather and climate events in the Midwest, see the weekly and monthly reports at the Midwest Climate Watch page.
- Southeast Region: (Information provided by the Southeast Regional Climate Center)
- Temperatures were near average to above average in Alabama, Georgia, Florida, and western North Carolina during November, while below-average temperatures were observed across central and eastern portions of the Carolinas and Virginia. Very few extremes in monthly mean temperature were recorded across the Southeast. Indeed, nearly 95 percent of the 196 long-term (i.e., period of record equaling or exceeding 50 years) stations observed November mean temperatures that were ranked outside their ten warmest or coolest values on record. San Juan, PR (1898-2017) and Miami, FL (1895-2017) tied their third warmest November mean temperature on record, at 81.8 and 77.3 degrees F (27.7 and 25.2 degrees C), respectively. On the 15th and 17th, San Juan tied its second highest daily minimum temperature on record for November, at 80 degrees F (26.7 degrees C). Miami tied its second highest count of 29 days during November with a maximum temperature at or above 80 degrees F, trailing only November 1986 (30 days). The warmest weather of the month occurred on the 3rd, as unusually warm and humid air surged northward ahead of an approaching cold front. Daytime maximum temperatures reached or exceeded 80 degrees F across portions of every state in the region. Augusta, GA (1874-2017) tied its fourth highest daily maximum temperature on record for November, at 87 degrees F (30.6 degrees C). In contrast, the coldest weather of the month occurred on the 20th, as a continental high pressure system ushered in unseasonably cold air from the northwest. Daily minimum temperatures fell below 32 degrees F (0 degrees C) across broad portions of every state in the region except Florida. On the 10th, Washington Dulles International Airport, VA (1963-2017) observed its first freeze during meteorological autumn, with a minimum temperature of 29 degrees F (-1.7 degrees C). This first freeze is the airport's second latest on record, trailing only November 11th, 2005. Roanoke, VA (1912-2017; 31 degrees F, -0.6 degrees C) and Lynchburg, VA (1893-2017; 28 degrees F, -2.2 degrees C) also observed their first freeze on the 10th, which is the fourth and fifth latest on record for these stations, respectively.
- Precipitation was well below normal across much of the Southeast region during November, with monthly totals ranging from 50 to less than 5 percent of normal. At least 31 long-term stations, with two or more located in every state, observed November precipitation totals that were ranked within their five lowest values on record, including Pensacola, FL (1879-2017; 0.09 inches, 2.3 mm), Fairhope 2 NE, AL (1918-2017; 0.14 inches, 3.6 mm), Moultrie 2 ESE, GA (1926-2017; 0.23 inches, 5.8 mm), and New Bern, NC (1948-2017; 0.42 inches, 10.7 mm). Several long-term stations tied their highest count of November days with no measurable precipitation, including Fairhope 2 NE, AL (28 days), Gadsden, AL (1953-2017; 27 days), and New Bern, NC (27 days). In contrast, well-above-normal precipitation occurred across portions of northern and southeastern Florida as well as Puerto Rico, where monthly totals were 150 to more than 300 percent of normal. On the 23rd, a slow-moving low pressure system produced 1 to more than 5 inches (25.4 to more than 127 mm) of rainfall across portions of northern and central Florida, with the greatest 24-hour precipitation total of 7.17 inches (182 mm) recorded by a mesonet station near Ormond Beach. Ocala (1892-2017) and Crescent City (1913-2017) observed their wettest and second wettest November day on record, with 4.80 and 3.52 inches (122 and 89.4 mm) of precipitation, respectively. Very little snowfall was recorded across the region during the month, with only a trace observed on Mt. Mitchell, NC.
- There were 53 severe weather reports across the Southeast during November, which is near the median monthly frequency of 45 reports during 2000-2016. Approximately 85 percent (45 of 53) of the severe weather reports were recorded on a single day (18th) during the month, and over 75 percent (34 of 45) of these reports occurred in Alabama. On the 18th, a squall line produced damaging straight-line winds across northern Alabama, with some of the highest measured gusts including 57 mph at Huntsville International Airport, 51 mph at Northeast Alabama Regional Airport in Gadsden, and 49 mph at Northwest Alabama Regional Airport in Muscle Shoals. Widespread downed trees and power lines were reported, while an auto parts store in Florence sustained major structural damage from wind gusts estimated at 80 to 90 mph, with two people injured inside. In addition, several buildings were damaged in the nearby town of Killen, including a drug store and the athletic field house at a high school. Only 3 tornadoes (1 EF-0 and 2 EF-1s) were confirmed across the region during the month, which is much less than the median frequency of 11 tornadoes observed during November. On the 18th, numerous homes were damaged and a well-constructed barn was destroyed along the 4.3-mile path of an EF-1 tornado that touched down in Lawrence County, AL.
- Abnormal dryness (D0) and moderate (D1) drought continued to expand in coverage across the Southeast during November. Indeed, the cumulative extent of abnormal dryness and moderate drought more than doubled within the region, increasing from 23 percent on October 31st to 58 percent on November 28th. Portions of every state were in moderate drought by late November, including south-central Virginia, central North and South Carolina, east-central and southern Georgia, west-central Alabama, and the eastern half of the Florida Panhandle. At least 20 percent of the USGS gages in Georgia, the Carolinas, and Virginia recorded well-below-normal (i.e., less than the 10th percentile) streamflows at the end of the month. Following periods of heavy rainfall during October, vegetable growers in southern Florida were able to resume preparing and planting their fields in early November, as warm and dry weather prevailed. A persistence of dry weather across much of the region during the month was beneficial for crop harvesting (particularly cotton, peanuts, soybeans, and hay) and the planting of winter grains. An exceptional yield of peanuts was reported in Alabama and Georgia, with some growers in Alabama having to ship out the harvested surplus after exceeding their local storage capacity. Mild temperatures in early November maintained the growth of warm season pastures in parts of the region, which allowed some livestock producers to continue grazing their cattle. However, below-average precipitation and insufficient soil moisture impeded the germination of winter grains across the region, prompting many ranchers to begin a supplemental feeding for their herds by the end of the month.
- 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 )
- Warm and dry conditions occurred in November across a broad area of the High Plains region to round out the fall season. Although the month started on a cold note, average temperatures by the end of November were above normal throughout western and central portions of the region. An impressive warm-up around Thanksgiving brought temperatures that were more reminiscent of early summer than late fall and broke numerous daily temperature records. The warmth was especially notable across Colorado and Wyoming, where several locations had a top 10 warmest November on record. Widespread dryness accompanied the warmth and precipitation was abysmal, as some parts of the region recorded less than 10 percent of normal precipitation. For instance, the majority of Kansas received less than 0.25 inches (6 mm) of precipitation the entire month.
- As a result of the warmth and dryness of November, a lack of snowfall was common across the region, and streamflows and topsoil moisture declined across the southern High Plains. The combination of these conditions contributed to drought spreading across portions of western Colorado and south-central Kansas, as well as the re-intensification of drought in western North Dakota where drought has been present since the early summer. Although warm temperatures caused mountain snowpack to suffer in Colorado, it fared well in the Upper Missouri Basin in Montana and Wyoming, where snowpack ended the month above average.
- As we enter the winter season, it is worth noting that a La Niña has developed for the second year in a row in the Pacific Ocean. La Niña can influence winter climate in the High Plains. For instance, a colder winter is often favored in the Northern Plains, while warmer and drier conditions are more likely in the Southern Plains. However, this has not always been the case, and other climate patterns can have a greater influence on winter climate but are not as predictable. To learn more about La Niña's influence in the Missouri Basin region, check out the link to a briefing in the Climate Outlooks section.
- Despite a cold start to the month, November was quite warm on the whole throughout the western and central High Plains. The warmest locations included Colorado and much of Wyoming, with temperatures averaging 6.0-10.0 degrees F (3.3-5.6 degrees C) above normal. The impressive warmth was record-breaking for Alamosa, Colorado and Rawlins, Wyoming, which had their warmest Novembers on record, and several other locations experienced November temperatures that were in their top 10 warmest.
- A dramatic warm-up in the latter half of November was largely responsible for much of the region ending the month with above-normal temperatures. This warm spell arrived just in time for the Thanksgiving holiday and lasted for several days. Daily average temperatures were as much as 20.0-30.0 degrees F (11.1-16.7 degrees C) above normal across parts of the region as widespread temperatures in the 70s were reported, and locations as far north as Valentine, Nebraska and Denver, Colorado even reached into the 80s! On the 26th, Cheyenne, Wyoming reported a high temperature of 71.0 degrees F (21.7 degrees C), which was its latest 70.0 degrees F (21.1 degrees C) temperature on record (period of record 1872-2017).
- As for fall temperatures, it was warm across most of the High Plains. The central and southern parts of the region experienced temperatures that were 2.0-3.0 degrees F (1.1-1.7 degrees C) above normal, while temperature departures exceeded 4.0 degrees F (2.2 degrees C) above normal in a large portion of Colorado, leading to a couple of records. For instance, Alamosa had its 2nd warmest fall on record, while Colorado Springs had its 4th warmest.
- Dry conditions prevailed over much of the High Plains during November, with the majority of the region only receiving 25 percent of normal precipitation, at best. The driest locations included Grand Junction, Colorado, which had its 3rd driest November on record, as well as parts of Kansas, where it was the 8th driest November on record for Topeka, Dodge City, and Goodland. The primary exception to the widespread dryness was Wyoming, where above-normal precipitation occurred in the northern and western portions of the state. In fact, Sheridan had its 8th wettest November on record.
- Coupled with above-normal temperatures, the widespread dryness caused some impacts around the region. For instance, most of the High Plains had below-normal snowfall in November. This 'snow drought' was most evident in Colorado. Only a trace of snow was recorded in Denver, and although it tied with many other years, it was the least snowiest November on record. In fact, it snowed more in Denver in October than it did in November! The lack of snow is concerning for recreational businesses such as ski resorts, and it has implications for spring runoff if this pattern continues. While it is still early in the snow season, the situation is worth watching.
- Another impact of the warmth and dryness of November was a rapid decline in soil moisture conditions across the High Plains. The greatest declines over the course of the month occurred in Nebraska and Kansas, where the percent of topsoil moisture rated short to very short increased from 14% to 32% in Nebraska and 18% to 39% in Kansas. Although the growing season is over, an adequate supply of soil moisture is needed going into winter to ensure enough moisture is available for spring planting. During the winter, the ground is often frozen and does not allow precipitation to enter the soil, so soil moisture cannot easily be recharged.
- As for the fall season, precipitation varied across the region. Two primary areas that experienced wet conditions included western and central Wyoming, as well as a swath from western Kansas up through central Nebraska into southeastern South Dakota. North Platte, Nebraska had its 3rd wettest fall on record, while it was the 6th wettest for Huron, South Dakota. Meanwhile, dryness existed throughout a large part of the Dakotas, eastern Kansas, and western Colorado. Grand Junction, Colorado tied for its 9th driest fall on record.
- Mountain snowpack got off to a good start in some parts of the region, but not in others this season. According to the U.S. Army Corps of Engineers, Missouri River Basin mountain snowpack above Fort Peck Reservoir and between Fort Peck and Garrison Reservoirs was above average as of the end of November. Snowpack in the Rockies of Wyoming was also above average. The good start to the snowpack season was largely due to early-season snowstorms that blanketed parts of the Upper Missouri Basin, and cooler temperatures in early November helped the snowpack stick around. However, snowpack was not faring so well in Colorado, particularly in the southern and western portions of the state. November was very warm and dry, and Snow Water Equivalent was less than 25 percent of median in that area. Luckily, snowpack season is just beginning, so there is plenty of time to catch up.
- Widespread dryness in November led to the expansion and intensification of drought conditions across portions of the High Plains. Region-wide, areas experiencing drought or abnormal dryness (D0-D4) increased from approximately 35 percent to 41 percent over the course of the month, according to the U.S. Drought Monitor.
- In the Northern Plains where drought has been present since early summer, conditions in Montana improved but worsened in western North Dakota. Western and southern Montana had a wet month, with some areas receiving as much as 300 percent of normal precipitation. Meanwhile, precipitation was scarce across western North Dakota and, as a result, moderate drought (D1) was re-introduced to the area. Elsewhere in the Northern Plains, drought conditions largely remained the same.
- Moderate drought was introduced to two other areas in the High Plains in November: western Colorado and south-central Kansas. In western Colorado, the combination of record-breaking warmth and the continuation of below-normal precipitation for the past several months took its toll on soil and vegetative health. Mountain snowpack in this region was below normal in November as well. In Kansas, November precipitation was abysmal, with much of the state receiving less than 25% of normal. The lack of precipitation caused below-normal streamflows in the south-central portion of the state, prompting expansion of drought conditions across the area.
- 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 temperatures were warmer than normal for most of the region. There were areas of 6 to 8 degrees F (3.33 to 4.44 degrees C) above normal in parts of Texas and panhandles of Texas and Oklahoma. Most of Texas, Oklahoma, Louisiana, and western and central Arkansas were 2 to 6 degrees F (1.11 to 3.33 degrees C) above normal. Eastern Arkansas, southeastern Louisiana, southern and central Mississippi, and most of Tennessee experienced slightly above normal temperatures. In contrast, parts of western Tennessee, northeast Arkansas, northeast Mississippi, and southwest Texas experienced slightly below normal temperatures. The statewide monthly average temperatures were as follows: Arkansas–53.60 degrees F (12.00 degrees C), Louisiana–61.70 degrees F (16.50 degrees C), Mississippi–59.60 degrees F (13.83 degrees C), Oklahoma–52.80 degrees F (11.56 degrees C), Tennessee–50.00 degrees F (10.00 degrees C), and Texas–60.40 degrees F (15.78 degrees C). The statewide temperature rankings for November were as follows: Arkansas (twentieth warmest), Louisiana (seventeenth warmest), Mississippi (twenty-fifth warmest), Oklahoma (tenth warmest), Tennessee (thirty-second warmest), and Texas (fifth warmest). All state rankings are based on the period spanning 1895-2017.
- Precipitation values for the month of November were below normal for most of the Southern Region. All of Arkansas and Oklahoma, most of Louisiana and Mississippi, and parts of Tennessee and Texas received 50 percent or less of normal precipitation. There were a few areas of 5 percent or below normal precipitation in northern, western, and southern Texas, southeastern Louisiana, and northern and southeastern Oklahoma. In contrast, parts of central and southern Texas and northern and central Tennessee received 110–150 percent of normal precipitation. There was an area of 200 - 300 percent above normal precipitation in extreme southern Texas. The state-wide precipitation totals for the month were as follows: Arkansas–1.09 inches (27.69 mm), Louisiana–1.51 inches (38.35 mm), Mississippi–1.21 inches (30.73 mm), Oklahoma–0.23 inches (5.84 mm), Tennessee–2.82 inches (71.63 mm), and Texas–0.71 inches (18.03 mm). The state precipitation rankings for the month were as follows: Arkansas (fourth driest), Louisiana (tenth driest), Mississippi (third driest), Oklahoma (fifth driest), Tennessee (thirty-second driest), and Texas (sixteenth driest). All state rankings are based on the period spanning 1895-2017.
- During November 2017, drought conditions worsened from October to extreme drought (D3) in southwest Arkansas and severe drought (D2) in southeast Oklahoma, north Louisiana, northeast Texas, and north, central, and southern Arkansas. Moderate drought (D1) developed or expanded in north central and southeast Oklahoma, north and central Mississippi, north, central, and southwest Louisiana, and east, central, and southern Texas. Areas experiencing abnormally dry conditions (D0) are east Arkansas, north and south Mississippi, south Tennessee, south Louisiana, central and northwest Oklahoma, and in parts of Texas. From October to November, no areas with drought conditions improved.
- Wind seemed to be the major meteorological hazard in November with roughly 44 wind events throughout the region, 37 of which occurred on November 18. There were four tornadoes during the month of November, all four occurred in Tennessee on November 18. The five other states did not have any tornado reports in November. There were 22 hail events reported in November, 19 of which occurred on November 3 throughout southeastern Arkansas, northwestern Mississippi, and northeastern Louisiana.
- The frontal passage on November 18 and 19 brought a strong squall-line across Tennessee and produced 3 tornadoes in Middle Tennessee (two in Davidson County and one in Trousdale County) and numerous high wind damage reports. There were no injuries reported with the tornadoes, but two injuries were reported from severe wind.
- On November 3, 2017, there were 19 hail events reported throughout southeast Arkansas, western Mississippi, and northeastern Louisiana. Three wind events were also reported, one specific event caused a tree to fall on a house in Ouachita, Arkansas.
- On November 6, 2017, there were three hail events reported in northern Arkansas and three wind events reported in Tennessee. The wind events caused downed trees in Williamson, Tennessee.
- On November 7, 2017, there were two wind events reported in Tennessee. One of the wind events, reported in Riceville, Tennessee, injured one person when a single wide mobile home was blown off of its foundation.
- On November 18, 2017, there were four tornadoes, 22 hail, and 40 wind events reported in Tennessee and four wind events reported in Mississippi. There were two injuries reported, one resulted from flying glass when windows were blown out of a home. The other injury occurred when a driver of a vehicle hit a tree.
- For more information, please go to the Southern Regional Climate Center Home Page.
- Western Region: (Information provided by the Western Region Climate Center)
- Temperatures were above normal across much of the West this month, and record-breaking in the Southwest. Several storm systems moved across the northern half of the region, producing near to well above normal precipitation, while the Southwest received little to no precipitation.
- Persistent high pressure over the Southwest resulted in record November temperatures. In Arizona, both Phoenix (71.2 F/21.8 C) and Tucson (69.1 F/20.6 C) recorded their warmest November on records that began in 1933 and 1946, respectively. Further east, Albuquerque, New Mexico, logged its warmest November in a 127-year record at 52.8 F (11.6 C), 7.9 F (4.4 C) above normal. In Utah, Salt Lake City also had its warmest November, reporting 47.8 F (8.8 C), 7.8 F (4.3 C) above normal. Records at Salt Lake City began in 1928. In Nevada, both Reno and Las Vegas experienced a record warm November with average temperatures of 48.7 F (9.3 C) and 62.8 F (17.1 C), respectively, roughly 6 F (3 C) above normal at both locations. High minimum temperatures, typically associated with lack of overnight cooling, had a strong influence on the average temperature records described above. All locations saw record minimum temperatures for November, though only Tucson and Phoenix saw record maximum temperatures as well. For other locations, maximum temperatures were among the top-10 but not record-breaking. Along the northern tier of the West, temperatures were near or slightly below normal.
- The northern Cascades and northern Rockies ended the month with near to above normal snowpack. The southern Cascades, Sierra Nevada, Great Basin ranges, and central and southern Rockies did not fare as well. For the Sierra and southern Cascades, snow levels generally remained high during storm events and limited snowpack accumulation at lower elevations (<7500 ft/2300 m). While it is still early in the season, this raises concerns of the beginning of a 'snow drought', the case when precipitation is near or above normal but snowpack is below normal.
- Very little precipitation was observed in the Southwest. San Diego, California, recorded only 0.02 in (<1 mm), 2% of normal and the 4th driest November since records began in 1939. In northern Arizona, Flagstaff recorded 0.01 in (<1 mm), <1% of normal and the 6th driest in a 125-year record. Albuquerque, New Mexico, reported no measurable precipitation, tied with 22 other years in its 127-year record. The lack of precipitation combined with above normal temperatures resulted in expansion of drought conditions in the Four Corners states; 73% of Arizona and 52% of Utah are now reporting moderate or worse drought in the US Drought Monitor as well as portions of western Colorado and western New Mexico.
- In Alaska, western and northern portions of the state experienced mild conditions while the Panhandle and southeast mainland were somewhat cooler and drier than average. Combined end of November sea ice extent for the Chukchi and Bering Seas was the lowest on record (since 1978), contributing to the mild temperatures in the north. Utqiagvik (Barrow) experienced its warmest November in a 98-year record at 17.2 F (-8.2 C), 16.5 F (9.2 C) above normal. In the southeast, Yakutat received 2.14 in (54 mm) of precipitation for November, 15% of normal and the 2nd driest in a 101-year record. To the south, precipitation was below to near normal across Hawaii, with some areas of the windward side of the Big Island experiencing above normal precipitation. Hilo recorded 20.53 in (521 mm) of rainfall, 132% of normal. The precipitation that occurred during October and November was sufficient to reduce drought impacts across the state. At the end of this month, only 26% of the state was experiencing drought conditions, compared with 47% at the end of October.
- November 13: Strong storm impacted western Washington: Strong winds associated with a cold front passage caused a variety of damage in western Washington. Winds up to 70 mph (113 kph) downed trees and caused power outages for more that 100,000 people. One woman was killed in Renton when a tree fell on her car. Five others were injured during the storm.
- November 22-27: Heat wave in southern California, Arizona: Strong high pressure resulted in temperatures more than 15 F (8 C) above normal around the Thanksgiving holiday in southern California. Many long-standing daily records were broken, and Camarillo reached 99 F (37.2 C) on the 22nd, setting a record for highest November temperature since records began in 1952. Services for the homeless were handing out water and advising people to seek shade. In Arizona, Tucson recorded a high of 92 F (33.3 C) on the 26th and 27th. This is the latest >90 F (32 C) date on record; the preceding record was set on November 22, 1924.
- For more information, please go to the Western Regional Climate Center Home Page.