Weather Extremes Dominate June Weather Headlines

The tornado frenzy that plagued Oklahoma in April and May completely subsided in June. After 102 tornadoes during the previous two months, including a record 55 in April, there were no tornado reports in June. However, the month didn’t lack dangerous weather, with twisters being replaced by historic rainfall, extreme heat and drought, and severe thunderstorms that left tens of thousands without power. On the night of June 25, storms plowed their way south through the state from the Kansas border in north-central Oklahoma into central Oklahoma, with winds up to 90 mph. These storms brought down power poles and trees, flipped vehicles, and tore off roofs. Some estimates place the number of Oklahomans left without power at nearly 100,000. The power outages created a dangerous situation in the following days, with extreme heat continuing across the state. The Oklahoma Mesonet site at Centrahoma recorded a heat index of 118 degrees on June 26, as did the Tulsa International Airport on June 29. Heat index values of at least 115 degrees were recorded 40 times by Mesonet sites during June, and at least 110 degrees another 235 times. The 118 degrees at Centrahoma is the sixth-highest heat index recorded by an Oklahoma Mesonet site during June in the network’s 30-year history. Grandfield holds the top June spot with 120 degrees on June 19, 2023.

A 1,000-year rainfall event occurred in the Panhandle on June 18-19, causing catastrophic flooding on the flat terrain of the region. Widespread totals of 6-9 inches were reported from the event that began late on the 18th and lasted through the morning of the 19th. The Goodwell Mesonet site recorded 7.67 inches of rain, with 7 inches falling in just over seven hours. A federal site near Goodwell recorded 8.64 inches, and an NWS cooperative site in Hooker measured 7.99 inches. The flooding led to road closures and impacted several homes and businesses, with some residents evacuated due to rising water levels. The magnitude of the rainfall event was also reflected in the June monthly rainfall totals, with the Guymon Municipal Airport leading the state at 10.3 inches, a rare feat for a semi-arid Panhandle station. The federal sites at Hooker and Goodwell came in second and third with 10.13 and 9.52 inches, respectively.

The statewide average rainfall total for June was 3.51 inches, 0.75 inches below normal, making it the 56th-driest June since records began in 1895. The historic rainfall in the Panhandle produced the largest surpluses in the state, propelling the region to its sixth-wettest June on record at 2.27 inches above normal. In contrast, west-central Oklahoma experienced its 12th-driest June with an average deficit of 2.48 inches. Individually, the Mesonet sites in the Panhandle saw surpluses of over 6 inches, while deficits in areas from west-central through north-central Oklahoma generally exceeded 3 inches. Mangum had the month’s lowest total at 0.32 inches. These patterns were similar to those of the January-June period, although the deficits from west-central through north-central Oklahoma increased to more than 6 inches. The statewide average rainfall total for the first six months of the year was 18.65 inches, 0.17 inches below normal, making it the 54th-wettest such period on record.

June’s statewide average temperature, as measured by the Mesonet, was 80.1 degrees, which was 2.8 degrees above normal and ranked as the 16th-warmest June since records began in 1895. Nineteen out of June’s 30 days saw at least one triple-digit temperature at one of the Mesonet’s 120 sites, with a peak of 110 degrees at Kingfisher on the 28th. The average temperature for the first six months of the year was 58.6 degrees, 2.4 degrees above normal, and ranked as the fifth-warmest January-June period on record. Altus and Erick led the state with 13 triple-digit readings through June, closely followed by Fairview with 12.

Flash drought continued to persist in June, despite improvements across far northwestern Oklahoma and the Panhandle. Drought coverage modestly increased from 15% of the state in early June to over 20% by month's end, according to the U.S. Drought Monitor. The area experiencing abnormally dry conditions—considered a precursor to drought on the Drought Monitor—expanded significantly from 12% to 32%. Looking ahead, the July Climate Prediction Center outlooks paint a bleak picture for Oklahoma, predicting a warmer and drier-than-normal month. Below-normal rainfall is particularly likely across southwestern Oklahoma. These outlooks are reflected in the CPC's July drought outlook, which forecasts continued drought persistence and development across all of Oklahoma, except for the western two-thirds of the Panhandle.