Oklahoma City sixth driest January and statewide, eighth driest January
Oklahoma Drought Expands During Dry January
By Gary McManus, state climatologist
February 3, 2014
Oklahoma became a weather battleground state during January.
A large upper-level ridge of high pressure entrenched over the western United States battled a deep trough of low pressure to the east for supremacy over the state’s weather. When the ridge gained the upper hand, temperatures at times rose into the 60s and 70s. Several locations even managed to reach 80 degrees on January 12, the highest temperature recorded during the month.
A westward push by the trough would result in another arctic blast and a plunge back to winter with highs struggling out of the 20s. Nowata reached a teeth-chattering low of minus 12 degrees following one of those cold fronts on January 6, the lowest temperature recorded by the Mesonet for the month. For those needing significant moisture, however, there was very little variety as dry weather dominated both sides of the skirmish. According to data from the Oklahoma Mesonet, the month finished with a statewide average of 0.29 inches, 1.16 inches below normal to rank as the eighth driest January since records began in 1895. Of the 120 Oklahoma Mesonet stations, five reported no precipitation during the month, and another 56 ended with a tenth of an inch or less.
Those stations left completely dry during January were Altus, Cheyenne, Erick, Hollis and Mangum.
The Mt. Herman Mesonet site led the state with 1.95 inches. Oklahoma City experienced its sixth driest January with 0.07 inches of precipitation. Tulsa was not much better with only 0.13 inches, the fourth driest January for that city. Complete monthly records for Oklahoma City date back to 1891 and 1894 for Tulsa. Combined with a dry December, the statewide average for the first two months of winter came up over 2 inches short for the 13th driest such period on record.
That same stretch was also decidedly cold. The statewide average temperature for December-January was 35.5 degrees, more than 2 degrees below normal and the 21st coolest on record.
One of the impacts of the near constant northwesterly upper-level air flow over the state was a loss of moist air return from the Gulf of Mexico. Without that humidity, let alone any significant precipitation, wildfire danger often soared in the face of dry air and strong winds. Those same conditions also quickened the pace of drought intensification, something not normally seen during the cool season. A bit more than 38 percent of the state was covered by at least moderate drought at the beginning of the month according to the U.S. Drought Monitor. At month’s end, however, that area had increased to nearly 47 percent. The most intense drought continued across southwestern Oklahoma and the Panhandle, a persistence of impacts that dates back more than three years. Much of the far southwest was considered in extreme-to-exceptional drought. Extreme drought had also begun to spread outward from the Texas County area in the Panhandle.
The Drought Monitor’s intensity scale slides from moderate-severe-extreme-exceptional, with exceptional being the worst classification.
Another visit from arctic air signaled a cold end to the month, and the frigid air was forecast to stretch well into the first week of February. The temperature outlook for February from the National Weather Service’s Climate Prediction Center (CPC) indicated slightly elevated odds of below normal temperatures across the northern two-thirds of the state. The precipitation outlook was noncommittal with equal chances of above-, below- and near-normal moisture amounts during February. With those long-range outlooks in mind, CPC’s U.S. Monthly Drought Outlook called for the drought across western Oklahoma to persist or even intensify for the month of February.
The three-month U.S. Drought Outlook released in mid-January also has the drought persisting or intensifying in the same area through the end of April.