Hail and Twisters Dominate May

After April’s stormy chaos, the first half of May brought a rare lull in Oklahoma’s spring severe weather season. Aside from an active kickoff on May 1 — featuring large hail, damaging winds, tornadoes, and flash flooding — the state experienced a quiet 16-day stretch, interrupted only by a single report of half-dollar-size hail in far southeastern Oklahoma on May 16. But the break didn’t last: severe storms returned on May 17 and dominated the remainder of the month.

2025 Tornadoes Reach Annual Average

At least 20 tornadoes were confirmed across Oklahoma in May, though that number may increase as National Weather Service (NWS) personnel continue their damage surveys. The preliminary total for January through May now stands at 58, nearly matching the state’s long-term annual average of 58.8 from 1951 to 2024. The January–May average is 41.8. Sixteen of the 20 tornadoes in May were rated EF1 or stronger.

Two of those tornadoes were the strongest of the year so far, both rated EF3. The first formed in the High Plains of Ellis County near Arnett on May 18, one of four tornadoes produced by the same parent supercell. The funnel was widely photographed as it moved over mostly open country, staying on the ground for 5.5 miles before lifting near Arnett’s outskirts. Peak winds were estimated at 145 mph, strong enough to strip bark from trees and toss a large shipping container 175 feet.

The second EF3 tornado struck southern Pittsburg County, carving a 16-mile path with peak winds estimated between 135 and 145 mph. At times up to 1.7 miles wide, the tornado damaged several homes and injured at least one person near the town of Pittsburg. Unlike the Ellis County storm, this tornado passed through more developed areas, contributing to its greater impact.

Hailstorms Cause Widespread Damage

Severe hailstorms pounded Oklahoma throughout May, producing widespread damage across multiple regions. One of the most extreme reports came from Ellis County on May 18, where 5-inch diameter hail — roughly the size of a DVD — fell from the same supercell that produced the Arnett EF3 tornado. Another bout of exceptionally large hail occurred near Hammon in Roger Mills County on May 26, with grapefruit-size stones reported.

Perhaps the most destructive hailstorm of the month struck on May 17, when a swath of 2- to 4-inch hail tore through central Oklahoma from near Chickasha to Oklahoma City. The hail shattered windshields, damaged roofs and siding, battered businesses, and shredded trees along its path. In total, Oklahoma’s National Weather Service offices received at least 228 reports of severe hail (1 inch or larger) during the month, with 79 reports involving hail the size of golf balls or larger. Hail 2 inches or greater — often considered the threshold for significant damage — was reported more than 40 times.

May saw at least 16 separate days with one or more severe hail reports across the state. The most active day was May 17, with over 60 hail reports logged statewide. Hailstones of 3 inches or larger were reported on five different days during the month, underscoring the unusually intense and frequent nature of this year’s spring hail activity.

May by the Numbers

Statewide average temperature: 66.7°F (1.7°F below normal), 35th-coolest May since records began in 1895
Temperature extremes: High of 101°F at Altus on May 13; low of 38°F at Eva on May 2
Warmest/Coolest locations: Highest monthly average temperature, 70.5°F at Altus; lowest, 59.7°F at Kenton
Statewide average precipitation: 5.82 inches (0.89 inches above normal), 35th-wettest May on record
Rainfall extremes: High of 15.52 inches at Wilburton; low of 1.75 inches at Lahoma
Rainfall totals greater than 5 inches: 67 instances recorded at the 119 Oklahoma Mesonet sites, including eight above 10 inches

Climatological Spring (March–May) by the Numbers

Statewide average temperature: 61.5°F (1.8°F above normal), 14th-warmest spring since 1895
Temperature extremes: High of 101°F at Alva on April 17 and at Altus on May 13; low of 18°F at Eva on March 5 and 16
Statewide average precipitation: 15.6 inches (4.3 inches above normal), ninth-wettest spring on record
Rainfall extremes: High of 29.57 inches at Wilburton; low of 3.51 inches at Eva

Drought Conditions Improve, July Outlook Promising

Drought coverage in Oklahoma dropped from 14 percent to just over 3 percent during May, according to the U.S. Drought Monitor. Severe drought, which had covered 7 percent of the state at the beginning of the month, was completely eliminated. This marked the lowest statewide drought extent in nearly four years, dating back to the onset of the broader drought episode in August 2021.

The Climate Prediction Center’s outlook for July shows significantly increased odds of above-normal precipitation across all of Oklahoma, with equal chances of above-, near-, or below-normal temperatures. The CPC’s drought outlook also projects that drought will likely be fully eradicated from the state by the end of the month.