Winter Storm — Northeast Bighorn Mountains, Wyoming

2021-10-11 to 2021-10-12 · Northeast Bighorn Mountains, Wyoming

Event narrative

Area SNOTELS reported 12-18 inches of snow.

Wider weather episode

The seasons first snow occurred during the second week of October. A surface low moved northeast out of the Four Corners region across Wyoming into the northern high plains. This allowed cold air to move south out of Canada while drawing moisture northward from the Gulf of Mexico. However, most of the cold air was due to dynamic cooling as a result of this powerful low. Heavy snow occurred across the entire Billings Forecast Area with the heaviest occurring across southeast Montana, as well as northern Wyoming.

Source: NOAA Storm Events Database, event_id 986194. Narrative written by the NWS forecast office that issued the report.