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Flash Flood — Delaware, PA

Sep 1, 2021

Post Tropical Cyclone Ida brought heavy rain to eastern Pennsylvania on September 1. Rainfall totals were as high as 5 to 10 inches. The heavy rain caused significant flash flooding, mainly in the southeastern part of the state. It resulted in widespread property damage. There were several fatalities.

Source: NOAA National Weather Service Storm Events Database (event 981450). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Delaware, PA

This event is one of many recorded floods in Delaware County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

View Delaware County flood data →

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