MISSOULA - Scattered mountain snow and valley rain will linger over mainly southwest Montana overnight and into Tuesday - generally staying along and south of I-90. Otherwise, expect a mix of clouds and sun with highs in the mid 40s to low 50s and breezy conditions at times during the afternoon.
On Wednesday, a closed low will begin to move into the region. Without the steering of the jet stream, this low will take its time moving through the area with the exact track unclear at this point. It will, though, usher in a southwesterly flow at first with highs in the 50s for Wednesday and increasing showers by the evening (maybe even a rumble or two of thunder!).
By Thursday, the cold air associated with this low will move into the region with snow levels now dropping to around 3,000'- 4,000' causing a good spring snow in many higher elevation valleys. The valley snow in western Montana will vary greatly, from a trace to up to 6" in some of the higher elevated valleys (like Georgetown Lake, Butte, Anaconda, Philipsburg, Seeley Lake, etc). Plan on 2"-6" for most area passes. Valleys that do see accumulation will see a heavy, wet nature of snow which will likely build up on trees, creating potential tree damage and power outages.
Precipitation looks to continue into Friday late morning with a mostly cloudy afternoon on tap and highs in the upper 40s.
As of now, the upcoming weekend will start of sunny with 50s and end partly sunny with mid 50s to low 60s.
