Thunderstorm Wind in Northumberland County, Pennsylvania

A line of severe thunderstorms producing wind gusts estimated at 60 mph knocked multiple trees down across West Chilisquaque Township.

A cold frontal passage during the evening hours of June 19, 2025 brought a broken line of showers and thunderstorms to central Pennsylvania in a moderately sheared and unstable environment. Ahead of the cold front, unstable conditions with ample moisture and shear in place allowed for multiple clusters of severe thunderstorms to form along the western mountains, and continue eastward as the evening progressed. One of these clusters moved northward from eastern Maryland into York and Lancaster counties, producing multiple instances of tree damage across southern portions of each county. A cluster of thunderstorms across Clearfield and Centre counties produced multiple instances of tree damage before continuing to cause isolated tree damage into the Middle Susquehanna Valley. The most widespread damage was observed in eastern Union County and northern Northumberland County, where more thunderstorms began to bow out and produce widespread straight-line wind damage.