Flash Flood — Hillsborough, New Hampshire

2025-08-13 · near Pine Hill, Hillsborough, New Hampshire

Event narrative

Very heavy rainfall associated with a severe thunderstorm dropped 2+ inches of rain in under an hour across the Nashua City area. The rainfall rates caused urban flooding with manhole covers popping off and flooding of Amherst Street in Nashua.

Wider weather episode

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.

View location on OpenStreetMap → (42.7700, -71.4700)

Source: NOAA Storm Events Database, event_id 1292525. Narrative written by the NWS forecast office that issued the report.