Flash Flood in Sandusky County, Ohio

Reports of widespread road closures due to flooded and impassable roadways in northeast Sandusky County. Radar estimated 3 to 3.25 inches of rain fell in a 2 to 3 hour period preceding the flash flood event. Total rainfall of 4 to 4.5 inches fell over a 5 hour period.

An anomalously-warm and moist air mass was in place across much of the Central Plains and Midwest, resulting in strong to perhaps extreme instability in addition to tropical-like precipitable water values exceeding 2.0 inches. The Lower Great Lakes region, specifically northern Ohio and Northwest Pennsylvania found itself on the eastern edge of this heat dome. Strong northwest flow aloft persisted along the periphery of the anomalously-warm and moist air mass, allowing for organized storms to develop across northern Ohio and Northwest Pennsylvania. A constant feed of moisture allowed these storms to maintain their intensity throughout the evening and overnight hours of Aug 23, 2023 and into the early morning hours of Aug 24, 2023 as they slowly pivoted southwest. Numerous flash flood warnings were issued with 3 considerable tags utilized throughout the course of the event. The hardest-hit areas were along the lakeshore between Toledo and Cleveland where there were several reports of 5 to 7 inches of rainfall. Elsewhere, generally 2 to 4 inches of rainfall was common, most of which fell in only a few hours. The area was on the edge of an extremely unstable airmass with sufficient deep-layer shear for organized convection.