December 2011 Climate Summary

For a printable version of the climate summary which includes more figures, data tables, and state summaries, click here. 

Temperature Summary

December was an interesting month across the High Plains Region.  The northern areas of the region were generally drier and warmer than normal and many areas did not experience a White Christmas.  The lack of snow cover, not just in the High Plains Region, but also in areas north into Canada, contributed to the unseasonably warm temperatures.  The Dakotas had the largest temperature departures in the region, ranging from near normal in the southwest corner of South Dakota to over 12 degrees F (6.7 degrees C) above normal in northern and northeastern North Dakota.  These warm temperatures caused many locations in the Dakotas to be ranked in the top 15 warmest Decembers on record.  For instance, Fargo, North Dakota had an average temperature of 25.3 degrees F (-3.7 degrees C), which was 12.8 degrees F (7.1 degrees C) above normal.  Fargo’s average temperature for December was ranked as the 3rd warmest and was just shy of the record which occurred in 1959 with 25.9 degrees F (-3.4 degrees C) (period of record 1881-2011).  Meanwhile, the western areas of the Region were generally colder than normal with temperature departures at least 6 degrees F (3.3 degrees C) below normal occurring in areas of southern Colorado and Wyoming.  A few locations in southern Colorado ranked in the top 10 coolest Decembers on record.  Lamar, Colorado had its 3rd coolest December on record with an average temperature of 21.8 degrees F (-5.7 degrees C).  While this was 8.5 degrees F (4.7 degrees C) below normal, it was not cool enough to beat the old December record of 18.1 degrees F (-7.7 degrees C) which occurred in 1924 (period of record 1893-2011).

Precipitation Summary

Precipitation was varied across the Region this month.  The Dakotas were generally drier than normal, with a few isolated pockets receiving above normal precipitation.  The ongoing dry conditions in eastern North Dakota led to the expansion of moderate drought conditions (D1).  Meanwhile, heavy rain and snow across Kansas and southern Colorado helped alleviate and in some cases eliminate drought conditions.

Precipitation was a welcome sight in drought-stricken areas of Colorado, Kansas, and southeast Nebraska.  This month, the heaviest precipitation in the Region fell in a large swath that stretched from southeastern Colorado, through Kansas, and into southeastern Nebraska.  The majority of the locations in this swath received 200-400 percent of normal precipitation, while clusters of locations in Kansas and Colorado received 400-800 percent of normal precipitation.  Numerous locations ranked in the top 10 wettest Decembers on record and many had precipitation totals which were ranked second and third wettest.  Wichita, Kansas had its 5th wettest December with 3.69 inches (94 mm) of liquid equivalent precipitation (period of record 1888-2011).  The wettest December occurred in 1984 with 4.71 inches (120 mm) of liquid equivalent precipitation.  Snowfall totals for the month of December also ranked in the top 10 across some areas of Kansas and Colorado.  At least one location had its snowiest December on record - Pueblo, Colorado.  Pueblo received 18.6 inches (47 cm) of snow this month, which beat out the old record of 18.2 inches (46 cm) set all the way back 1913 (period of record 1888-2011).

December 19-20 was an active period as a major winter storm brought heavy rain, sleet, and snow to Colorado and Kansas.  Heavy snow was accompanied by strong winds which created blizzard conditions in some locations.  According to the National Weather Service in Dodge City, Kansas, snow drifts of 8 to 10 feet (243 to 305 cm) were also reported.  Some of the heaviest snow fell in southeastern Colorado where some interesting records were set.  Lamar, Colorado received 19.0 inches (48 cm) of snow on December 20th and set an impressive new daily snowfall total for that day.  This snow total well exceeded the old record of 10.0 inches (25 cm) set in 2006 (period of record 1893-2011).  The snowfall on the 20th also set a new record as the highest one-day snowfall total for any day in December.  Interestingly, the 19.0 inches (48 cm) of snow was also the second highest one-day snowfall total for any day of the year in Lamar.  The record one-day snowfall occurred October 26, 1997 when 22.0 inches (56 cm) fell in Lamar.

2011 ended on a windy note as damaging winds affected Wyoming, Colorado, Kansas, and Nebraska.  Wind gusts over 60 mph (97 km/hr) were widespread and there were even reports of winds over 100 mph (161 km/hr) in some of the mountainous areas of Colorado.  The high winds led to dangerous driving conditions on the open highways and some structural damage.  According to the National Weather Service in Cheyenne, Wyoming, vehicles, buildings, and signs were damaged as a result of the high winds.

Climate Outlook

La Niña conditions are present in the equatorial Pacific and are expected to continue through winter.  The temperature outlook indicates a higher probability of above normal temperatures for most of Kansas, the southeast corner of Colorado, and the far southeast corner of Nebraska.  A higher probability for below normal temperatures exists for the western half of North Dakota, northwestern Wyoming, and the northwest corner of South Dakota.  The precipitation outlook indicates a higher probability of above normal precipitation for the majority of Wyoming, western portions of the Dakotas, and northwestern Colorado.  Meanwhile, western Kansas and southeastern Colorado have a higher probability of below normal precipitation.  Equal chances of above, near, or below normal precipitation and temperature are predicted elsewhere in the Region.  The seasonal outlooks combine the effects of long-term trends, soil moisture, and when applicable, the El Niño Southern Oscillation cycle (ENSO).  More information about these forecasts can be found here.

Drought Watch

The U.S. Drought Monitor had many changes this month.  Storm systems bringing beneficial rain and snow to Colorado and Kansas have led to the erasure of all exceptional drought conditions (D4) in those states.  In addition, extreme drought conditions (D3) were also erased in Colorado.  Other major changes occurred in Kansas as well, as all drought conditions were eliminated in the north and the drought conditions that remain have contracted to the south somewhat.  Southeastern Nebraska also benefitted from the December precipitation as drought conditions were erased for a large portion of that area.  Meanwhile, due to an ongoing lack of precipitation in North Dakota, moderate drought conditions (D1) have expanded northward in the eastern side of the state.  Drought conditions in South Dakota remained largely the same since last month, with the exception of a slight expansion of abnormally dry (D0) and D1 conditions in the southeast.  According to the U.S. Seasonal Drought Outlook drought conditions in portions of the Dakotas, Nebraska, Colorado, and western Kansas were expected to persist, while drought conditions in eastern Kansas were expected to improve.