Hail in Erie County, Pennsylvania

Hail up to half dollar-size about three-miles ENE of downtown Erie.

A surface low moved east-southeastward from northwestern Lower MI to the southeastern shore of Lake Huron during the late morning through mid-evening of the 20th. Simultaneously, the low's warm front swept northeastward across northwestern PA to central Lake Ontario and central NY, and the low's trailing cold front moved generally eastward from northwestern Lower MI and southern Lake Michigan to southern Lake Huron and near the western shore of Lake Erie. Moderate to strong MUCAPE and effective bulk shear, respectively, were present just ahead of the surface warm front and within the warm sector.

A multicell thunderstorm in vicinity of the surface warm front persisted northeastward across northern portions of Erie County, including the city of Erie, during the early afternoon and produced severe hail and damaging convective wind gusts. A semi-discrete supercell then moved generally eastward across southern Erie County during the late afternoon through early evening and produced severe hail, including large hail of 2-inches in diameter in the Corry area. Following the supercell, a line of multicell thunderstorms persisted generally eastward and southeastward across northwest Pennsylvania and produced isolated straight-line convective wind damage in Conneautville, Crawford County.