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Flash Flood — Hillsborough, NH

Jun 6, 2025

A stationary front stalled over southern New Hampshire on the evening of June 6 into midday on June 7th. Repeated rounds of heavy rain and thunderstorms brought up to 4 inches of rainfall to areas across Merrimack and Hillsborough Counties between 3 and 7 PM. The heavy rain with rates measured over 2 inches per hour at times, was sufficient to cause flash flooding with multiple roads flooded, some with washouts, and some property damage. Numerous severe thunderstorms also developed on the after

Source: NOAA National Weather Service Storm Events Database (event 1252505). 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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