EF1 tornado in Allegheny County, Pennsylvania

A storm survey performed by the National Weather Service confirmed that a brief EF-1 tornado, with maximum winds of 105 MPH, occurred near Aten Road in Findlay Township, just west of I-376 and adjacent to the Pittsburgh International Airport.

The tornado touched down north of Aten Road, where a trailer on blocks in a parking lot was overturned, with some tree damage nearby. The tornado then progressed southeast, snapping at least 15-20 trees along the northern side of Aten Road. This area represented the strongest damage, where the 105 MPH wind was

assigned. A nearby outbuilding lost a metal roof in several pieces. One portion fell on the interstate, while another blew over the interstate and landed roughly a quarter-mile downwind. The tornado caused additional tree damage near the Edgeworth Security and Marriot hotel buildings. The tornado likely then lifted, as no other appreciable damage was noted other than the previously noted roof pieces that were blown downstream.

Potent low pressure tracked across the Upper Midwest from May 7th into May 8th, pushing an occluded boundary across the Upper Ohio Valley. Strong warm and moist advection kept conditions favorable for convection into the overnight hours, with high levels of shear and a surface trough also supporting storm development. Cyclic supercell structures supported a few instances of straight line wind damage, as well as three tornadoes in southwest Pennsylvania. One of these ended up being one of the stronger and more significant tornadoes in the region's recent history, a high-end EF2 that ultimately tracked across 15 miles and three states.