Drought Ends for Much of Oklahoma
Thu, Mar 22, 2012
Heavy rain associated with this week’s slow-moving storm system brought one hazard back to the state, even as it was ending another. The abundant moisture produced flooding in eastern and central Oklahoma, but also alleviated drought impacts that had plagued the state over the last 19 months. The result was a much-improved Oklahoma drought picture. According to the latest U.S. Drought Monitor report released Thursday morning, the area of the state completely free of drought or abnormally dry conditions rose from 27 percent last week to 63 percent this week. At the drought’s zenith in September 2011, the entire state was suffering some level of drought. At that point, having just exited the hottest summer on record for any state dating back to 1895, 69 percent of Oklahoma was mired in exceptional drought, the U.S. Drought Monitor’s worst category.
According to data from the Oklahoma Mesonet, rainfall totals of 4-6 inches were common throughout the eastern half of the state for Monday through Thursday morning. Estimated totals from radar indicate some localized areas in the northeast received more than 8 inches. Virtually the entire state received at least an inch of rain, with more general amounts of 2-4 inches spread throughout western and central Oklahoma. The Mesonet site at Pryor led totals with 6.95 inches. With rain continuing to fall, only three of the Mesonet’s 120 stations failed to record at least an inch of rainfall, and unfortunately they are located in areas of the state still hit hard by drought impacts. Kenton has had a paltry-but-welcome quarter-inch of moisture in the far western Panhandle. Its neighbor Boise City and Tipton in far southwestern Oklahoma received around three-quarters of an inch. Fifty-nine Mesonet sites recorded at least 3 inches of rain through Thursday morning, with 33 of those reporting more than 4 inches.
The statewide average going into Thursday morning stood at 4.3 inches, 2.1 inches above normal. That ranks the month already as the 10th wettest March on record with more than a week left to go, and the 13th wettest January-March period. The drought was just getting a toehold in March 2011, which ended as the eighth driest on record with a statewide average of 0.71 inches. The relief this March continues the momentum of drought eradication that began in October 2011. Since that time, also known as the start of the water year, the state has received an average of 17.3 inches of rain, a surplus of 3.6 inches. The water year runs from Oct. 1-Sep. 30. The water year thus far is the 12th wettest on record, compared to the same period last year, which was the seventh driest.
The outlooks for April-June from the National Weather Service’s Climate Prediction Center are uncertain about Oklahoma’s precipitation chances through that period. They indicate equal chances of below-, above- or near-normal precipitation, meaning no clear climate signal exists to tip the forecast in one direction. Two of those possibilities would be favorable for Oklahoma. Anything but below normal rainfall will continue to alleviate existing drought impacts, and prevent more drought from developing.