Powell saw up to 3.74 inches of rain in just 72 hours around Aug. 11, part of a month that ranks as the Columbus area's second-wettest August since 1879.
Delaware County 911 issued a flood watch on Wednesday, Aug. 19, then upgraded to flood warnings on Thursday, Aug. 20, as a second wave of storms moved through. The National Weather Service (NWS) issued a flash flood emergency for the Franklin County area at about 4:45 a.m. on Aug. 20, with Delaware County included in the broader alert until 7:15 a.m., NBC4 reported.
Orange Township's North Orange Aquatic Center closed on Tuesday, Aug. 11, the day a derecho swept central Ohio, according to an Orange Township notice. NWS rainfall data showed Powell gauges recorded between 2.99 and 3.74 inches during the 72-hour period around Aug. 11–13, according to NWS-compiled totals reported by WLWT.
A month for the record books
The month's final tally, compiled by NBC4 meteorologist Ben Gelber, put Columbus at 9.94 inches of rain for August. That trails only August 2003 (11.46 inches) in city records dating to 1879 and is nearly three times the 3.74-inch monthly average. Measurable rain fell on 15 of 17 days between Aug. 7 and Aug. 23.
The storm total of 3.87 inches at John Glenn International Airport on Aug. 19–20 set a record for 24-hour August rainfall, breaking a mark that had stood since 1915. The week of Aug. 14–20 brought 6.30 inches, the wettest seven-day stretch in Columbus since late August 2003.
The Aug. 11 derecho
The NWS office in Wilmington confirmed the Aug. 11 storm system met the criteria for a derecho, with damaging winds of at least 58 mph across more than 400 miles. The system formed over Iowa that morning and raced southeast across Indiana, where at least seven people died in flooding.
Peak gusts hit 82 mph at John Glenn International Airport and 70 mph at The Ohio State University Airport in northwest Columbus. The storm knocked out power to about 110,000 AEP Ohio customers in central Ohio, according to AEP Ohio President Marc Reitter.
Columbus Mayor Andrew Ginther declared a city emergency on Wednesday, Aug. 12. "For the first time in the division's history, every unit of the Columbus Division of Fire was in service responding to calls for service to folks in the city," Ginther said at a news conference reported by WOSU.
Fourteen tornadoes touched down across Ohio on Aug. 11 alone. The NWS confirmed additional tornadoes on Aug. 28 after field surveys, including an EF0 in Upper Arlington that flipped a vehicle on Interstate 71, according to NBC4. Most of the widespread damage in the Columbus area came from straight-line winds rather than tornadoes, the NWS said, with gusts in some corridors estimated between 90 and 100 mph, 10TV reported.
Flooding closed I-70
The worst flooding struck early on Aug. 20. Slow-moving thunderstorms dropped 2 to 4 inches on already-saturated ground. The South Fork Licking River near Buckeye Lake crested at 882.81 feet on Friday, Aug. 21, the second-highest level on record. Both directions of Interstate 70 closed.
Ohio's preliminary August tornado count reached 19, surpassing the previous record of 18 set in 2023. The state's 2026 total stands at 44 confirmed tornadoes, twice the annual average.
By the final week of August, water levels in swollen creeks and rivers receded, and cooler, drier weather gave residents a window to clear storm debris.
