Heavy Snow — Northern Coos, New Hampshire

2018-11-26 to 2018-11-27 · Northern Coos, New Hampshire

Event narrative

Steady snow began on the evening of the 26th. Southeast flow downsloping off the White Mountains delayed significant snowfall accumulation for much of the early part of the event. Light accumulations occurred through the morning of the 27th. Once flow became westerly and upslope enhanced snowfall began accumulations began to pile up quickly north of the notches. Total snowfall ranged from 6 to 12 inches, though additional accumulation continued in upslope snow showers into the 28th.

Wider weather episode

This winter storm began as a blizzard over the Midwest. The storm moved into the eastern Great Lakes early on the 26th and snow broke out over northern New England that afternoon and evening. Secondary low pressure developed in the vicinity of Cape Cod on the evening of the 26th helping to ensure cooler air remained trapped across much of New Hampshire. Surface temperatures hovered within a couple degrees of freezing, but aloft temperatures were much colder. As a result snowfall was heavy and wet, and very dependent on elevation. While lower elevations mixed at times with sleet, freezing rain, and rain, the higher terrain remained predominantly snow and significant accumulations occurred. Low pressure slowed to a crawl on the 27th and snow continued into the 28th, although the bulk of the accumulation was from the evening of the 26th to the afternoon of the 27th.

Source: NOAA Storm Events Database, event_id 788036. Narrative written by the NWS forecast office that issued the report.