Feb 24, 2016
A strong low pressure system moving north through the Great Lakes region, combined with its associated warm front and cold front, copious amounts of moisture, and low level jet, produced strong to severe thunderstorms, heavy rain, flash flooding, and stream flooding in Eastern Pennsylvania late Wednesday afternoon and evening, February 24th, with stream flooding continuing into Thursday, February 25th. Most electric outlets reported thousands of power outages.
Source: NOAA National Weather Service Storm Events Database (event 613080). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Philadelphia County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.