Heavy Snow — Northern Carroll, New Hampshire

2019-01-09 · Northern Carroll, New Hampshire

Event narrative

Snow and light mixed precipitation changed over to moderate to heavy snowfall during the morning of the 9th. This band of snow pivoted over the area through the early afternoon, before moving east. Low pressure moving into New Brunswick kept winds northwest over the area into the overnight, and low level moisture forced over the mountains resulted in some additional upslope snow accumulation.

Wider weather episode

Overnight on the 8th a warm front lifted into the Northeast and stalled along the coast. A strong upper level vorticity maximum crossed the the stalled boundary on the morning of the 9th and led to rapid cyclogenesis along the New England coastline. Low pressure moved northeast along the Maine coast before moving into New Brunswick. While it was cold enough to snow in the mountains, warmer temperatures in the low to mid levels allowed for precipitation to begin as a mix of sleet, freezing rain, and rain to the south. As low pressure strengthened, heights aloft lowered and precipitation transitioned to heavy snow as it exited the area. Low level moisture and northwest flow behind the departing system kept upslope snow showers going into the morning of the 10th.

Source: NOAA Storm Events Database, event_id 794292. Narrative written by the NWS forecast office that issued the report.