November Brings Early Taste of Winter to Oklahoma

November is considered a fall month climatologically, but it certainly did its best to look like a winter month during 2013. Emphatically cooler than normal, thanks mostly to a frigid outburst by Mother Nature during its final 10 days, November was punctuated by an early cool-season snowstorm that dumped more than a foot of snow across southwestern Oklahoma. According to data from the Oklahoma Mesonet, the statewide average temperature for the month ended 1.8 degrees below normal at 46.5 degrees, the 33rd coolest November since records began in 1895. November was the eighth month during 2013 to finish with below normal temperatures. Prior to that, 28 out of the 34 months between April 2010 and January 2013 had been warmer than normal. The January-November statewide average of 61.1 degrees is the 40th coolest such period on record at half of a degree below normal, standing in stark contrast to last year's mark of 65 degrees over the same period. The fall season itself, however, was actually 0.2 degrees above normal and ranked as the 59th warmest on record. The lowest temperature recorded by the Mesonet was 9 degrees from Alva on the ninth, and the highest temperature of 85 degrees occurred at Altus on the 16th.

Moisture was plentiful in a few select areas, but scarce for most. The statewide average precipitation total as measured by the Mesonet came in at 1.64 inches, more than an inch below normal, to rank as the 47th driest November on record. The most notable exception was drought-parched southwestern Oklahoma, a result of their late-month wintry blast, although far southeastern Oklahoma saw some hefty precipitation totals as well. Other than those lucky few, the rest of the state saw deficits of 1-3 inches. Far northwestern Oklahoma was particularly dry with less than 20 percent of normal November rainfall. Fall was also dry with a statewide average of 7.22 inches, 2.8 inches below normal, to rank as the 45th driest on record. The Mesonet station at Idabel led the state with 6.52 inches while Freedom recorded a meager 0.18 inches.

The wintry precipitation actually came in two successive waves. The first storm brought a light glaze of ice to the state on the 22nd and 23rd and wind chills down into the single digits. The more powerful storm struck on the 24th and 25th with snow, sleet and freezing rain falling over a large area, creating widespread traffic problems and scattered power outages. National Weather Service (NWS) cooperative observers at Altus, Hobart and Vinson all recorded 13 inches of snow during the storm on November 24 and 25, and the Mangum observer was close behind with 11 inches. Widespread totals of 4-6 inches were reported across other parts of southwestern Oklahoma. Some snow spread to the north and east from the storm, but the rest of the state saw precipitation mainly in the form of rain, sleet and freezing rain. Oklahoma City saw less than an inch of snow during the storm and Tulsa recorded a trace.

Very little change occurred in drought conditions during November according to the U.S. Drought Monitor. There was an increase in drought intensity across far southwestern and west central Oklahoma, but a bit of a decrease across south central Oklahoma. At month's end, 31 percent of Oklahoma remained in some intensify of drought on the Drought Monitor, almost entirely within the western one-third of the state.

The December precipitation outlook from the NWS' Climate Prediction Center (CPC) indicates increased odds of below normal moisture for Oklahoma. The outlook for temperature is much less certain with equal chances of below-, above- and near-normal temperatures during December. An extended visit by an arctic air mass does look likely for late in the first week and into the second week of the month, so that might be enough to tip the odds to the cool side. CPC's Monthly Drought Outlook for December calls for drought to persist across those areas of Oklahoma where it is already in place, but also for more development across far western Oklahoma. CPC's winter outlook for the December-February period sees increased odds of above normal temperatures, but no definitive outlook for precipitation.

 

Link to the December temperature and precipitation outlooks from the Climate Prediction Center:
http://www.cpc.ncep.noaa.gov/products/predictions/30day/

Link to the December-February temperature and precipitation outlooks from the Climate Prediction Center:
http://www.cpc.ncep.noaa.gov/products/predictions/long_range/seasonal.php?lead=1

Link to the December U.S. Drought Outlook:
http://www.cpc.ncep.noaa.gov/products/expert_assessment/monthly_drought.pdf

Link to the latest U.S. Drought Monitor map for Oklahoma:
http://droughtmonitor.unl.edu/data/pdfs/20131126/20131126_OK_trd.pdf

 

Word Document

PDF Document