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Flash Flood — Merrimack, NH

Jul 29, 2023

A stalled frontal boundary and surface low pressure began to slowly lift northward into the southeast New Hampshire through the Midcoast of Maine on the afternoon of the 29th. Showers and thunderstorms developed along the boundary and moved eastward. Since the system as a whole showed very little forward progression, multiple rounds of showers and thunderstorms ended up moving across the same locations multiple times, on top of already saturated soils. This ended up leading to multiple instances

Source: NOAA National Weather Service Storm Events Database (event 1124064). 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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