Winter Storm — Southern Coos, New Hampshire

2023-12-03 to 2023-12-04 · Southern Coos, New Hampshire

Event narrative

Precipitation began around midday on the 3rd as a wintry mix of rain and snow. Downsloping easterly flow, which was both warmer and drier than on the upslope side of the White Mountains, kept precipitation type mainly rain or very light snow. The east facing slopes stayed predominately snow. This led to a large range in snowfall totals from the higher terrain of the White Mountains to the west near the Connecticut River. Eventually steady snow tapered to upslope snow showers, which continued for most of the day on the 4th. Snowfall totals ranged from 10 inches in the higher terrain, locally as high as 15 inches in the Presidentials, to 2 inches along the Connecticut River.

Wider weather episode

Early on the 3rd a stalled frontal boundary was draped across southern New Hampshire and near the coast of Maine. Low pressure slowly developed along the southern end of the front and rode north along the Appalachians through the day on the 3rd. Low pressure occluded during the evening on the 3rd, with a secondary low pressure developing south of Nantucket. The bulk of the precipitation came with the initial push of warm air advection, winding down early in the morning on the 4th. However an inverted trough hanging back to the northwest of the low center extended light snow through much of the day on the 4th.

Source: NOAA Storm Events Database, event_id 1146310. Narrative written by the NWS forecast office that issued the report.