Heavy Snow — Lower Clark Fork Region, Montana

2025-12-05 to 2025-12-06 · Lower Clark Fork Region, Montana

Event narrative

Between 12 and 18 inches of snow fell in the mountains and at Lookout Pass. The Montana Department of Transportation required chains at Lookout Pass. Other snow amounts include 1.5 inches at Heron and 3.6 inches near Trout Creek.

Wider weather episode

A potent atmospheric river moved into the Northern Rockies between December 4 and 7, delivering significant mountain snowfall. While the event began with heavy snow across the region, a transition to rain and freezing rain occurred in some valleys.

Source: NOAA Storm Events Database, event_id 1304063. Narrative written by the NWS forecast office that issued the report.