Bone-chilling cold on tap for Halloween week

Halloween skeletons beware; forecasters say it will be bone-chilling cold this week across Northwest Montana.

A surge of frigid air is set to arrive along the Continental Divide on Monday, ushering in valley snow followed by single-digit low temperatures across the region.

A winter weather advisory issued Sunday for the Flathead and Mission valleys calls for 1 to 3 inches of snow by Monday evening. Three to 5 inches of snow is possible in the West Glacier Region.

Wind gusts as high as 40 mph will stir up Flathead Lake, with wave heights up to 4 feet possible. Valley wind chill values Monday night could dip below zero.

After the initial snow and wind blast, unseasonably cold air settles in for the week.

Overnight lows Tuesday through Thursday mornings look to be below zero along the Divide, with single digits for many valleys of Western Montana, the National Weather Service in Missoula warned in its Sunday forecast.

The coldest day will be Tuesday, with highs expected to remain in the 20s.

Trick-or-treaters should plan for temperatures in the 20s and teens on Thursday night.