Aug 10, 2018
Showers and thunderstorms formed along a nearly stationary boundary that crept southeastward from the Great Lakes. Precipitable water values of around 1.6 inches and weak steering flow along the boundary led to a few areas of training thunderstorms. Rainfall amounts of 1.5 to 3.0 inches on already saturated ground led to several areas of flash flooding in Washington, Allegheny, and Westmoreland Counties. The worst flooding was near Herminie, where up to 14 homes were impacted and a mobile hom
Source: NOAA National Weather Service Storm Events Database (event 779387). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Washington County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.