Stormy pattern brought an unusually high number of August tornadoes
COLUMBUS, Ohio (WCMH) -- A southward shift of the jet stream has introduced a cooler, less humid airflow that will put an end to a stormy late summer pattern.
A pair of thunderstorm systems that formed on the edge of a steamy air and rolled across the northern half of Ohio on consecutive nights last week brought heavy rain, vivid lightning, torrential rain and embedded tornadoes.
Nearly 700,000 customers lost power in the second round of powerful storms by early Friday, including about 300,000 in Ohio. Wind gusts reached 75 mph in southern Michigan, and localized downburst winds were estimated as high as 80-90 mph in Columbiana County, Ohio, "comparable to many weaker tornadoes," according to the National Weather Service survey conducted by the Pittsburgh office.
The first collection thunderstorms dove south-southwest from Lower Michigan into northern Ohio on Wednesday night and early Thursday, dropping 2 to 4 inches of rain during the night. A top total of 7.1 inches fell at Kipton in Lorain County.
Less than 24 hours later, a second complex formed in central Michigan in the heat of the afternoon, taking a southeasterly trajectory over Lake Erie into northeast Ohio and western Pennsylvania overnight. Northern Ohio experienced high winds, hail and tornadoes between 10 p.m. and 2 a.m. Storm motions were extraordinary along the congealing squall line, moving at speeds of 60-70 mph.
The National Weather Service in Cleveland confirmed a total of 10 tornadoes touched down along a line from Ottawa and Erie counties to the east side of Cleveland, tearing up trees, toppling power lines, and damaging homes and buildings.
Clusters of storms marching across northeast Ohio into western Pennsylvania after midnight were accompanied by high winds and several more tornadoes, as far south as Medina County. In addition, seven tornadoes were confirmed in southern Michigan Thursday evening, and one in southwestern Pennsylvania early Friday.
Thunderstorm systems
Normally, tornado season in Ohio peaks in the spring (April-June), when conditions are the most favorable for severe weather, due to contrasting temperature, pressure and wind conditions in a zone of high instability (heat, moisture).
However, July and August this year have been noteworthy for a large number of fast-moving thunderstorm complexes that produced short-lived circulations conducive to tornadoes, in addition to discrete supercell thunderstorms that developed strong rotation.
Five tornadoes were confirmed earlier in the month on Aug. 12 in north-central and southeast Ohio, including EF1 tornadoes in Kenton and southeast of Athens (90 to 100 mph winds) that caused areas of damage. A weak tornado occurred in Butler County on Aug. 14.
Video of a funnel cloud outside of Athens, Ohio, on Aug. 12, 2023, that touched down southeast of Athens and traveled 2.3 miles, blowing over trees near several homes. (Video courtesy Adam Fowler)
A preliminary total of 16 tornadoes has been reported by Weather Service offices around Ohio this month--an August record. So far in 2023, a count of 54 tornadoes is more than double the state average (21) for an entire year, based on the past 30 years of records (1993-2022).