Flash Flood — Sullivan, New Hampshire

2023-09-08 · near North Charlestown, Sullivan, New Hampshire

Event narrative

An un-named tributary to the Sugar River flows from south to north out of Hubbard Hill came out of banks on the 8th. Floodwaters damaged the intersection of Roberts Road and Borough Road. An unofficial weather station in the community measured over 2 and a half inches, with instantaneous rain rates peaking over 4 inches an hour around 5 PM. Radar estimated a storm total rainfall between 2.5 to 3.5 inches over the Charlestown area.

Wider weather episode

Localized flash flooding was observed after a slow moving front brought multiple rounds of showers and thunderstorms across Massachusetts into southern New Hampshire. The airmass was very moist and supported rainfall rates over 2 inches per hour.

View location on OpenStreetMap → (43.3054, -72.3715)

Source: NOAA Storm Events Database, event_id 1131275. Narrative written by the NWS forecast office that issued the report.