Oklahoma Drought Picture Worsens During November

Drought surged during November with a return to the dry, warm and windy weather pattern that Oklahoma has become accustomed to over the last couple of years. According to the latest U.S. Drought Monitor report, the amount of extreme to exceptional drought rose from 72 percent last week to 91 percent this week. The state had not seen that amount of extreme to exceptional drought since late September. Other than a small but persistent area of moderate drought in far northeastern Oklahoma, the entire state remained in at least severe drought according to the report. The Drought Monitor’s intensity scale slides from moderate-severe-extreme-exceptional, with exceptional being the worst category. The bulk of that increase came across areas in southern and eastern Oklahoma that had been categorized in severe drought since September.

Through November 28, the statewide average temperature stood at 52.4 degrees according to preliminary data from the Oklahoma Mesonet, approximately 3.4 degrees above normal. That would rank this November as the 12th warmest since 1895, although a couple of warm days to finish the month could increase that ranking. November is set to become the 26th month out of the last 32 to finish warmer than normal, dating back to April 2010. Oklahoma’s 2012 January-November average temperature remains approximately two-tenths of a degree ahead of 1954 in a race to break the record for warmest calendar year.

The month has also been exceedingly dry, a continuation of what the state has seen since May. The Mesonet’s statewide average total for the month will finish at 0.57 inches, more than 2 inches below normal and the 21st driest November on record. It has been 63 days since the Mesonet site at Buffalo has seen a day with at least a quarter-inch of rain. Other parts of western and southern Oklahoma have gone from 40-60 days with a similar lack of rainfall. It has been 60 days since the Hollis Mesonet site has recorded a tenth of an inch of daily rainfall and as many as 47 days in the Panhandle. This November stands in stark contrast to last year’s version, which ended as the 12th wettest on record at nearly 2 inches above normal. The current span of particularly dry weather extends farther back than the beginning of November. According to preliminary data from the Oklahoma Mesonet and the National Climatic Data Center, the statewide average rainfall total for May through November was 13.48 inches, the second driest such period on record in Oklahoma. The only drier May through November was 1952’s 13.34 inches.

The combination of wind, warmth and lack of rainfall accelerated the loss of moisture from the state’s soils and reservoirs, and impeded the progress of the winter wheat crop. The November 26 weekly crop update from the USDA’s Oklahoma office of the National Agricultural Statistics Service noted that the state’s topsoil and subsoil moisture conditions were rated 95 percent and 97 percent poor to very poor, respectively. The report also indicated that only 13 percent of the winter wheat crop was rated as good, with one percent in the excellent category.  Eleven of the state’s major reservoirs are at less than 70 percent of normal capacity, with an additional eight being below 80 percent. Lake Altus-Lugert is in the worst shape at 17 percent of capacity.

There is very little rain in the forecast, although light amounts are expected across eastern Oklahoma associated with a frontal system early next week. Longer range outlooks from the National Weather Service’s Climate Prediction Center (CPC) indicate increased odds of more warm and dry weather in store for December. The CPC also sees increased odds of above normal temperatures lasting through the winter, but little confidence in any prediction on precipitation. December, January and February are the three driest months for Oklahoma. 

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