Slippery start to the week, warming up by Tuesday and Wednesday

Much chillier air on the horizon
Posted at 8:49 AM, Dec 20, 2021
and last updated 2021-12-20 10:49:31-05

Sunday night: Snow will continue throughout the night for areas south of route 200. Helena will pick up another 2-4 inches throughout the night. On and off light snow showers can be expected in Great Falls. Temperatures will fall into the lower single digits, with wind chills as low as -15 degrees.

Monday: Light snow may briefly work back into Great Falls after daybreak through 10am. Scattered snow showers are possible east of Great Falls and for the Hi-Line. There is a slight chance some light freezing drizzle could mix in with the snow in these areas as well. High temperatures will rise to the mid 20s. Mostly cloudy to cloudy skies can be expected otherwise. Overnight lows will be in the 10s.

Tuesday: High pressure develops in eastern Montana providing us with mostly sunny and warmer conditions on Tuesday. It will also be on the breezier side with gusts as high as 40mph possible Tuesday afternoon. High temperatures climb into the upper 30s and low 40s. Temperatures fall to either side of 30 degrees Tuesday night.

Wednesday: High pressure begins to break down on Wednesday ushering in mostly cloudy skies. It will remain breezy with gusts up to 35mph possible. Temperatures will climb into the lower 40s. Overnight lows will fall to around 20 degrees.

Thursday: A few snow showers are possible, especially towards Helena and in the Rockies. High temperatures will be in the mid 30s followed by overnight lows in the single digits. Mostly cloudy to cloudy skies otherwise.

Christmas Eve: A storm system and associated arctic cold front will move into northwestern Montana and slowly moves south throughout the day. Heavy mountain snow is likely with snow also making its way into the lower elevations of western Montana. Major impacts are not anticipated in central Montana outside of crashing temperatures and gusty winds. We will keep you updated on the status of this storm and its impacts on holiday travels. Otherwise, high temperatures will be in the low to mid 20s but again, falling throughout the day. Subzero overnight low temperatures with dangerous wind chills expected.

Christmas Day: Snow will continue in western Montana, with lighter snow showers possible for central Montana. Mostly cloudy to cloudy skies expected. High temperatures in the single digits and low teens. Overnight lows will be -10 to -20 degrees with even lower wind chills possible.

Sunday: High temperatures will only be -5 to 5 degrees with chillier temperatures for areas north of Great Falls and in the mountains. Dangerously cold wind chills can be expected throughout the entirety of the day. Otherwise, partly sunny to mostly cloudy skies.

Weather update (December 19, 2021)