Winter Weather — Southern Clinton, Pennsylvania

2024-12-04 · Southern Clinton, Pennsylvania

Event narrative

SNOW SQUALL. RWIS data indicated a rapid drop in visibility to a quarter of a mile with roadways becoming snow covered quickly in a snow squall. Air and surface temperatures were already below freezing before the snow squall, but data indicated a 4 degree drop in surface temperatures during the squall. This squall resulted in a multi-vehicle incident on Interstate 80 involving 10 tractor trailers and 3 to 4 passenger vehicles, closing the roadway for multiple hours.

Wider weather episode

Snowfall began during the early morning hours of December 5, 2024 across the northern tier with warm air advection within an enhanced low level jet ahead of a cold frontal passage beginning to overspread snowfall across central Pennsylvania. Enhanced frontogenetic forcing and instability in the lower levels allowed for some snow squalls to form across the Laurel Highlands and Middle Susquehanna Valley, with some snow bands continuing into the Lower Susquehanna during the morning commute. Northwesterly flow behind the cold frontal passage allowed for lingering lake effect snow showers across portions of northwestern Pennsylvania, with heavy lake effect snow continuing through December 6th. A snow squall along Interstate 80 in southern Clinton County caused a multi-vehicle accident with 10 tractor trailers and 3 to 4 passenger vehicles, closing the roadway for multiple hours and injuring two motorists.

Source: NOAA Storm Events Database, event_id 1222057. Narrative written by the NWS forecast office that issued the report.