Aug 19, 2011
A slow moving cold front and a moist unstable airmass combined to produce scattered severe thunderstorms and flash flooding across eastern Ohio and Western Pennsylvania. Flash flooding was deadly in Pittsburgh when approximately 2.5 inches of rain fell in a very urbanized area just east of downtown Pittsburgh on Washington Blvd in just under an hour. This resulted in four fatalities and up to 15 water rescues.
Source: NOAA National Weather Service Storm Events Database (event 334799). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Allegheny County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.