An Arctic system moving through the state could impact holiday travelers, especially on mountain passes. The National Weather Service forecast calls for snow, high winds, and subzero temperatures in parts of Montana and Idaho this week.
Northwestern Montana:
The strongest Arctic system of the season thus far will bring snow, blowing snow, and subzero wind chills to northwest Montana. Snow is expected to begin Monday night and should continue throughout the day Tuesday. Snow will gradually decrease Tuesday afternoon for valleys as gusty northeast winds move in. Wind gusts of 50 mph will be possible for areas near Bad Rock canyon Tuesday afternoon. Due to the strong push of cold air, a flash freeze could be possible on Tuesday. Gusty winds and snow will likely continue over Marias pass through Tuesday night. Subzero wind chills will begin Tuesday night and cold temperatures will likely stick around through next weekend.
Southwest/West-Central Montana:
The strongest Arctic system of the season thus far will bring snow, blowing snow, and bitterly cold temperatures to southwest and west central Montana. Snow is expected to begin Tuesday afternoon and should continue through Wednesday for southwest Montana. The combination of blowing snow and cold temperatures will cause slick travel conditions with near zero visibility and the potential for a flash freeze Tuesday afternoon/night. The greatest snow and wind will be over mountain passes along the Continental Divide but even valleys will see snow and hazardous roadways. Bitterly cold temperatures are expected starting Wednesday night especially over southwest Montana and will likely continue through the weekend.
Idaho:
The strongest Arctic system of the season thus far will bring snow, blowing snow, and cold temperatures to north central Idaho. A mix of mountain snow and valley rain will begin Tuesday morning but will eventually transition to all snow by Tuesday evening. Mountain passes will see the biggest impacts where moderate to heavy snow and blowing snow is possible Tuesday afternoon and night. Most of the snow is expected to dissipate Tuesday night with the exception of Lemhi county where moderate snow will continue throughout Wednesday. Cold temperatures are expected starting Wed night and Thursday.
