MISSOULA — Looking at another cloudy, cool and wet day across the northern Rockies. Not heavy rain, but off and on light showers can be expected throughout the day Tuesday. Highs will top out in the 50's to low 60's.
The first official day of summer may be Saturday, however, mountain snow will move back into the forecast tonight for southwest Montana.
Snow levels will drop to around 5,000 ft. Tuesday night into Wednesday morning. Mountain Passes such as Skalkaho, Lost Trail, Homestake and MacDonald will generally receive up to 6" of slushy accumulation.
For those planning to recreate above 6,000 ft. during this time frame, be prepared for around 6"-to-12" of snow. Mountain ranges such as the Anaconda and Flint Creek Ranges could pick up close to 20".
The valleys of southwest Montana will stay all rain during this time, however, snow can not be ruled out for the higher elevation valleys such as Butte, Georgetown Lake, Anaconda and Philipsburg. Northwest Montana will stay mostly dry tonight.
By the afternoon Wednesday, snow will turn to light rain for all elevations across western Montana. Highs will once again top out int he 50's to low 60's.
Temperatures will start to warm Thursday and Friday. Scattered rain showers will remain in the forecast as well. Highs will be in the low to mid 60's Thursday and upper 60's to low 70's Friday.
High pressure will build in for the weekend leading to sunshine and much warmer weather with temperatures returning to the 80's by Sunday.