Thunderstorm Wind — Belknap, New Hampshire

2025-07-20 · near Gaza, Belknap, New Hampshire

Event narrative

Significant tree damage was located in Sanbornton, NH that was consistent with a wet microburst. Numerous eye witnesses expressed that the strongest winds occurred with the heaviest downpour. Damage was variable in the downburst area with a general southeast fall direction to the trees being observed. There where two distinct pockets of damage that took hundreds of trees down, to include pine, oak and maple. Trees where both uprooted and snapped. In addition, hundreds of other trees where downed on the edges of the damage area, but damage was more sporadic in nature. Some structural damage did occur, but was mostly confined to sheds and shelter structures. A few vehicles were also damaged due to trees falling on them. Additional damage was likely further in the woods, but was not accessible for the damage survey. An estimated 500 trees were either snapped or blown down in the damage area.

Wider weather episode

A surface cold front dropping down from Canada interacted with a very hot and unstable airmass in place across the state. Significant shear aloft allowed for some organized thunderstorms. One storm in particular in Sanbornton brought widespread wind damage due to wet microbursts.

View location on OpenStreetMap → (43.5027, -71.5920)

Source: NOAA Storm Events Database, event_id 1288503. Narrative written by the NWS forecast office that issued the report.