August Heat Adds To Hottest Summer Since 2011

August’s heat and drought appeared ferocious at first, with widespread triple-digit temperatures and moisture deficits throughout the first half of the month. A strong cold front signaled a pattern change, however, and the heat settled into more seasonable levels for the last half of the month. On the whole, August was still well above normal and contributed to the hottest climatological summer seen in the state since 2011. There was just enough rainfall to provide some drought relief near the end of the month, but not before the coverage of severe drought had expanded to its highest levels in the state since March 5, 2013. The Aug. 9 U.S. Drought Monitor report had 92.5% of the state in at least severe drought, but that level had diminished to 88% at month’s end. Impacts reported to the Oklahoma Mesonet included dry farm ponds, cattle sell-offs, a lack of hay and grazing, and crop failures. There was some severe weather associated with the rainy periods in the form of damaging winds and hail, but the more significant impacts came in the way of heavy rains. Widespread flash flooding occurred over Aug. 22-23 and again on the 29th in parts of central and southern Oklahoma, and necessitated road closures and water rescues for stranded motorists.

The statewide average precipitation total was 2.13 inches according to preliminary data from the Oklahoma Mesonet, 1.1 inches below normal and ranked as the 40th driest August since records began in 1895. As is usually the case in Oklahoma, some parts of the state fared much better than others. South central and southwest Oklahoma saw their 38th and 39th wettest Augusts on record, respectively. Meanwhile, the north central and northeast regions suffered through their third and ninth driest Augusts, respectively. Waurika led all Mesonet sites with 8.88 inches for the month while Red Rock’s gauge measured a measly 0.17 inches. Thirty-two of the Mesonet’s 120 sites failed to reach at least an inch of rain during August, and 28 sites saw 3 inches or more. The climatological summer—June 1 through Aug. 31—ended as the 30th driest on record at 7.48 inches, 3.21 inches below normal. Deficits of 2-8 inches were common across the state, with a few very localized surpluses of 2-8 inches. The first eight months of the year were equally as dry with a statewide average of 21.34 inches, 3.91 inches below normal and ranked as the 40th driest January-August on record.

The statewide average temperature finished at 81.9 degrees, 1.1 degrees above normal and ranked as the 46th warmest August on record dating back to 1895. Temperatures peaked early in the month with Hollis hitting the month’s high mark at 110 degrees on Aug. 4. Triple-digit temperatures occurred on 18 of August’s 31 days, and were recorded 826 times at Mesonet sites during the month. The month’s lowest temperature of 51 degrees was recorded at Eva on the 25th. August’s heat topped off an uncommonly hot summer, which ended with a statewide average of 82.7 degrees, 2.6 degrees above normal and ranked as the ninth warmest June-August on record. That also marks the summer as the warmest in Oklahoma since 2011’s 86.8 degrees, which tied with Texas that year for the hottest summer in any state and any year since records began in 1895. This summer’s temperatures topped out on July 19 at Mangum at 115 degrees, tying the Mesonet’s all-time highest reading with six other sites dating back to 1997. Oklahoma had not seen a temperature that high since Kingfisher hit 115 back on Aug. 1, 2012. The heat continued to mount for 2022 with the first eight months of the year finishing at 63.5 degrees, 0.8 degrees above normal and ranking as the 23rd warmest January-August on record.

The September temperature and precipitation outlooks from the Climate Prediction Center aren’t full of doom and gloom at least, but they aren’t exactly rosy, either. The outlooks show equal odds of above-, below-, and near-normal temperatures and precipitation over the bulk of the state. There are increased odds of above normal temperatures in the western Panhandle and above normal rainfall in far southeastern Oklahoma. CPC’s September drought outlook calls for some improvement in the drought across roughly the southeastern one-third of the state, but persistence across the remainder of Oklahoma.