EF1 tornado in Westmoreland County, Pennsylvania

The team observed tree damage along Matson Road that was judged to be non-tornadic thunderstorm wind. The damage in this area consisted of a couple of trees snapped more than halfway up from their base. The team noticed more significant damage starting at Austraw Road, where the tornado likely touched down. Several trees were either uprooted, or their trunks were snapped halfway up. A small cattle shelter also collapsed in this area.

The tree damage continued up and down the hillside to the east toward McCurdy Trail and Berkeley Road. Concentrated damage occurred around two homes in this area, mainly to trees. A mix of very large hard and softwood trees was snapped low on the trunk and up high, while others were uprooted. Another area of concentrated tree damage was noted in the fields east of Berkeley down to Coalpit Creek, where the tornado lifted. The team also observed that some trees in this area were stripped of their bark. Much of the tree damage was in the EF-1 range, with maximum wind speed of 100 MPH estimated.

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.