Winter Weather — Northern Blaine County, Montana

2024-12-18 to 2024-12-19 · Northern Blaine County, Montana

Event narrative

Blaine County Sheriff announced on social media that, per DOT, only emergency traffic was permitted on US-2 and MT-241. A social media post from broadcast media stated that the order was due to the combination of icy roads, snow, freezing rain, and lowered visibility from strong winds.

Wider weather episode

A robust trough digging southeastward from the Pacific Northwest brought a belt of strong mid and low-level westerly flow across the majority of the region December 18. Given the favorable timing of the strongest flow and cold front, winds were easily able to mix to the surface. A respectable pressure gradient also developed across the area, which helped a few sites reach high sustained winds. In northeastern areas the wind took longer to develop, eventually needing the surface low to pull away from AB toward SK. This propelled a front through the area that brought both strong winds as well as rain that fell onto very cold surfaces, resulting in slick roads.

Source: NOAA Storm Events Database, event_id 1220929. Narrative written by the NWS forecast office that issued the report.