Heavy Snow — Northern Coos, New Hampshire

2019-03-21 to 2019-03-23 · Northern Coos, New Hampshire

Event narrative

Snow began late on the 21st but did not become heavy at times until early on the 22nd. With a warmer late season boundary layer a combination of dynamic, evaporational, and upslope cooling allowed precipitation to stay mostly snow in the mountains of North Country New Hampshire. Lower elevations snowfall was wetter in nature and compacted down to lower amounts. Snowfall totals ranged from 8 to 12 inches in the higher elevations, with amounts closer to 6 to 8 inches in valleys.

Wider weather episode

On March 21st a an upper trough was swinging through the Great Lakes, becoming negatively tilted over the Northeast. Surface low pressure formed off the Mid Atlantic in response and quickly began to deepen at all levels. Snow developed ahead of the low pressure late on the 21st and continued into the 23rd. Low pressure eventually tracked into central Maine, which introduced some warmer air and mixed precipitation towards the end of the event.

Source: NOAA Storm Events Database, event_id 808628. Narrative written by the NWS forecast office that issued the report.