Drought surged across Oklahoma as the driest September since 1956 took its toll on the state’s landscape. The amount of drought in the state remained largely unchanged through September at approximately 99%, but the intensity of that drought increased dramatically according to the U.S. Drought Monitor. Extreme and exceptional drought, the Drought Monitor’s two worst categories, jumped from 47% on Aug. 30 to 64% at the end of September, the highest such levels seen in the state since Feb. 19, 2013. Exceptional drought alone rose to 17%, its highest level since May 8, 2018.

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.

The seemingly impenetrable heat wave and dry spell that had punished Oklahoma since early June continued through nearly all of July, giving Oklahoma the type of scorching hot weather unseen in the state since the brutal summers of 2011 and 2012. A strong cold front snuck through the heat dome’s defenses near the end of the month to bring some relief, but the damage was done. The combination of hot weather, a lack of significant moisture, and relentless sunshine combined to plunge Oklahoma into flash drought that had covered the entire state by the end of July.