Oklahoma Sees March Rainfall Divide

Oklahoma’s oddly persistent caste-like rainfall pattern—with those to the north and west of Interstate 44 seeing near-record dryness and those to the south and east experiencing abundance—continued during March. Rainfall totals to the northwest of I-44 were generally a half-inch or less, while amounts of 5-8 inches were quite common to the southeast. Ten Oklahoma Mesonet sites in far northwest Oklahoma failed to record more than a tenth of an inch of rain for the month, with another 17 stuck below the quarter-inch line on the rain gauge. The 0.07 inches at the National Weather Service’s observing site in Ames broke the previous record of 0.05 inches for their driest March set back in 1900. The observer in Weatherford recorded a trace for the month. The persistent dry weather continued to hinder early spring green up in that half of the state and exacerbate dangerous wildfire conditions. The month’s final day saw winds gusting up to 77 mph combine with relative humidity in the teens and single digits to create the prime ingredients for a wildfire outbreak. At least 36 homes were destroyed by a wildfire in Logan County according to local and state Emergency Management officials, as well as at least seven homes in Washington County. Another three homes were burned in Oklahoma City. Several other homes were either damaged or destroyed by wildfires that day across the state. The Oklahoma State Department of Health reported 32 injuries related to the fires and the accompanying weather. There was one confirmed tornado during the month—an EF1 twister near Broken Bow on March 2—bringing the 2023 total to 18, well ahead of the January-March average of 4.9. It was also the first month since October 2022 with a below average tornado total.

The statewide average precipitation total of 3.04 inches was 0.26 inches above normal and ranked as the 38th wettest March since records began in 1895. March Mesonet rainfall totals ranged from a 13.22 inches at Cloudy to a scant hundredth of an inch at Woodward. Forty-six of the Mesonet’s 120 sites recorded at least 4 inches for the month, all within the southeastern half of the state. The statewide average precipitation total for the first 3 months of the year was 6.66 inches, 0.62 inches above normal and ranked as the 39th wettest January-March on record. January-March totals across the southeastern half of the state ranged generally from 10-20 inches, with Mt. Herman leading the way at 24.22 inches. Surpluses for the 3-month period ranged from about an inch to more than 12 inches in that part of the state. The northwestern half of the state fared much worse with totals of less than an inch to 3 inches, and deficits of an inch to 3 inches. Eva had the lowest total with 0.38 inches. 

Oklahoma spent much of March with below normal temperatures, including a downright frigid Spring Break. The statewide average temperature for the month finished at 50 degrees, 1.2 degrees below normal and ranked as the 60th warmest March since records began in 1895. Temperatures ranged from 90 degrees at Altus and Mangum on March 11, to 5 degrees at Eva on March 19. Oklahoma suffered a statewide hard freeze on March 18-19 with low temperatures in the teens and 20s, although some areas in northwest Oklahoma saw temperatures drop into the single digits. The January-March period finished at 45.5 degrees, 1.5 degrees above normal and ranked as the 22nd warmest such period on record.

Drought coverage in Oklahoma dropped from 67% at the end of February to 54% at the end of March according to the U.S. Drought Monitor with nearly all of those improvements coming in the southeastern half of the state. The amount of extreme-to-exceptional drought—all within the northwestern half of the state—remained about the same at 37%, however. The highest intensity category alone rose from 9% to 13% during the month. Prospects for drought reduction during April look slim according to the Climate Prediction Center. CPC’s temperature outlook calls for increased odds of above normal temperatures across the entire state. The precipitation outlook indicates increased odds for above normal precipitation across the southeastern one-half of the state. The April drought outlook shows the current drought conditions persisting through April.