Through Tuesday night, the heaviest snow with falls reaching between 1 and 2 feet will hit the eastern slopes of Montana and southern Alberta, Canada.
Significant snowfall will also cover Great Falls.
Other substantial falls of snow will happen mostly away from major highways and population centers between the northern Rockies and the Cascade Range in Oregon and Washington. Highways most likely to intersect areas of significant snowfall through the morning Wednesday will be I-15 and I-90.
Story by AccuWeather.com Senior Meteorologist Jim Andrews.
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