Worried about cold weather over the Christmas weekend? Move to Alaska now.
A snow and wind storm heading toward western Montana should send temperatures to the single digits or below while dumping inches and feet of snow in the valleys and mountains along the Continental Divide by the end of the week. Meanwhile, Anchorage, Alaska, expects to see a high of 36 on Christmas Eve.
National Weather Service meteorologist LeeAnn Allegretto said a wet flow off the Pacific Coast will run into a rush of cold air blowing out of the Arctic Circle through most of the week.
“The two are a perfect recipe for snowfall just about everywhere,” Allegretto said Monday. “This is a classic setup. The cold is creeping down the Rocky Mountain Front, while that moisture coming straight off Pacific is feeding into that cold air and causing nonstop generation of snowfall.”
Missoula will take awhile to get in gear, with highs in the upper 30s through Tuesday evening and a high probability of rain. That should shift to snow Tuesday night as the temperatures begin falling. By Thursday, the high will be 24, and by Christmas Eve on Sunday we’ll struggle to break zero.
But higher elevations have already started feeling the storm. Lookout Pass and the Interstate 90 corridor recorded heavy snowfall on Monday, with 6 to 10 inches forecast in the first wave followed by another 18 to 24 inches Tuesday into Wednesday. Winds there could gust to 45 mph, resulting in blowing and drifting snow.
Farther north, Tuesday could dump 12 to 18 inches of snow on U.S. Highway 2 at Marias Pass, with up to 4 feet accumulation there by Wednesday. Bad Rock Canyon, Essex, Polebridge and the Montana Highway 83 corridor between Bigfork and Swan Lake can expect wind gusts up to 45 mph.
Great Falls meteorologists warned that damage to trees and power lines could be expected as snow accumulations of 1 to 2 feet in the foothills accompany wind gusts up to 65 mph. The heaviest snow is expected Tuesday east of the Continental Divide.
Once the arctic air settles into the valley bottoms west of the Divide, the continued wet air should keep the snow coming through Christmas. Allegretto said Lookout Pass ski area could get more than 2 feet of snow by mid-week, while the Lost Trail area at the southern end of the Bitterroot Valley should collect at least a foot. The strong winds mean snow could pile up in troublesome formations in the mountains.
“We have avalanche watches already posted in the area,” Allegretto said. “The backcountry threat will grow substantially in coming days.”