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Flash Flood — Merrimack, NH

Jul 16, 2023

On the evening of July 15th isolated thunderstorms developed across southern New Hampshire. Storm movement mitigated flash flooding across the state, except for the city of Manchester where multiple storms traveled directly over the city on the evening of July 15th. Up to 2��� fell in an hour over the urban city area. The intense rainfall rates lead to rapid run-off and caused localized urban street flooding with water due to run-off entering some building structures. Lighter showers p

Source: NOAA National Weather Service Storm Events Database (event 1123750). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Merrimack, NH

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

View Merrimack County flood data →

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