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Flash Flood — Montgomery, MD

Jul 31, 2025

A slow moving cold front combined with a highly unstable atmosphere along with tropical moisture to produce slow moving thunderstorms with heavy rainfall. Some of these storms trained over the same areas, resulting in scattered to numerous instances of flash flooding. Total rainfall amounts in areas with flash flooding averaged two to four inches, though some localized amounts up to six inches were observed.

Source: NOAA National Weather Service Storm Events Database (event 1270216). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Montgomery, MD

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

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