The Flathead Valley and West Glacier areas are expected to catch the brunt of weather systems bringing heavy snow, cold and high winds starting Saturday evening.

“It’s pretty grim, especially for Northwest Montana,” National Weather Service meteorologist Peter Felsch said during a Friday teleconference.

The weather will result from a southward arctic cold front colliding with moisture moving from the Pacific. Idaho’s Clearwater Mountains and the northern Continental Divide are the first areas expected to be impacted by snowfall.

A winter storm warning was issued for the West Glacier and Middle Fork Flathead corridors from 11 a.m. Saturday through 5 a.m. Monday.

During that period, snow accumulations of 12 to 22 inches are forecast, along with strong gusty winds that will result in “local whiteout conditions in east-west canyons,” Felsch said.

Areas expected to be impacted include Bad Rock Canyon, Essex, Marias Pass, Polebridge and Montana 83 to Swan Lake, according to the Weather Service.

A winter storm watch has been issued for the Flathead and Mission valleys for the same period.

“We think there’s a good chance of seeing 8 to 12 inches” in the valleys, Felsch said.

From Saturday into Sunday, he added, temperatures will dip into the single digits throughout the region with dangerous wind chills reaching 20 to 30 below zero.

Temperatures will start moderating Monday, with lows in the teens to 20s and highs in the 30s into next week, Felsch said.