WEATHER DISCUSSION: Bitterly cold temperatures settle into North Central Montana starting today. High temperatures ranged below zero and up to the single digits for the region, though the wind chill made temperatures feel a lot colder, mostly in the negatives. Expect cloudy skies and low temperatures tonight to be very cold and below zero, with wind chills as low as -50, prompting Cold Weather Advisories and Extreme Cold Warnings for northern and eastern portions.
Pacific moisture is overrunning deep Arctic airmass at the surface, prompting the cold and snowy conditions. This will set the stage for a prolonged period of light to moderate snowfall tonight through Tuesday.
The overall long duration of the event will lead to significant snowfall accumulations across all elevations southwest of the Browning to Lewistown line and northeast of the Butte to Bozeman line.
The biggest concern throughout the period will be strong and gusty north winds that will begin on Monday as the Arctic airmass surges south.
These strong and gusty north winds will lead to the potential for significant blowing and drifting of the falling/fallen snow.
In addition to the threat for accumulating snow, a very strong surface high will slowly drift southeast from Canada. Bitterly cold temperatures will accompany this surface high with the coldest temperatures and wind chills residing over the plains of Central and North Central Montana.
Currently, Tuesday night/Wednesday morning looks to be coldest night as skies slowly clear, with areas along the Hi-Line having the highest probabilities of reaching or exceeding 40 degrees below zero.
Upper-level ridging will slowly build east towards the Northern Rockies during the last half of this upcoming week, which will help to moderate temperatures across Southwest through North Central Montana.
Increasing southwest to west winds will accompany the ridge during that period, especially strong and gusty along the Rocky Mountain Front.
