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Flash Flood — Hillsborough, NH

Aug 13, 2025

The region was experiencing well above normal temperatures, with high temperatures reaching the low to mid-90s. This created a very warm, humid, and unstable atmosphere. A pre-frontal surface trough moved into NH on the afternoon of August 13th, triggering numerous thunderstorms, a few of the storms became severe in nature. In addition, very heavy rain fell in Nashua area, causing some minor urban flooding.

Source: NOAA National Weather Service Storm Events Database (event 1292528). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Hillsborough, NH

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

View Hillsborough County flood data →

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