Next weather maker late Thursday
Ample moisture will be available this week as a moist west northwest Pacific flow continues across western Montana. A few rain and snow showers are possible late Tuesday night, especially around Missoula and west central Montana. A few more rain, snow and graupel showers Wednesday and Thursday. Lows in the upper 20s to lower 30s. Highs in the 40s.
Moisture will combine with a Canadian cold front late in the day Thursday through Friday. The combination of rain and snow, gusty winds and blowing snow, will create travel concerns Thursday night into Friday morning. Snowfall of 4 to 12 inches in the the mountains, including some of the passes. Some valleys will see accumulating snow. It will depend how much arctic air makes it into the area. Models indicate the coldest air stays east of NBC Montana.
Snow levels will begin to increase Friday as the arctic air retreats.
Widespread rain will develop Saturday. Runoff due to rain and snowmelt will lead to a noticeable rise in the streams and rivers. Rainfall from Thursday through the weekend will be moderate to heavy, with generally a half to 2 inches with locally up to 3 in some areas.
Milder early next week with highs in the upper 40s to lower 50s.