Strong winds mixed with an incoming arctic air mass produced a “complicated” storm in Northwest Montana over the weekend, alternating between freezing rain and snow, with drifts and unstable conditions plaguing roadways throughout the region.
With the storm subsiding as of late Monday, lower elevations in the area are now expected to experience a couple days of milder, more consistent weather, with snow showers in the mountains, followed by the possibility of another storm hitting the valley beginning the evening of Thursday, Feb. 8.
Dan Zumpfe, a meteorologist with the National Weather Service in Missoula, said the arctic air mass and strong winds first hit the Marias Pass area late Friday and Saturday, before pushing into the greater Flathead Valley over the weekend into Monday morning.
“There for a while it was pretty bad, at least in the northern half of the Flathead Valley,” Zumpfe said. “We don’t usually see that strong of winds with an arctic air mass coming into Western Montana.”
A number of areas throughout the valley accumulated between 8 and 16 inches of snow in a 36-hour period, while also experiencing freezing rain.
“It was a complicated storm that really evolved over time,” Zumpfe said. “Quite a bit of blowing and drifting, especially in the Friday and Saturday period over Marias Pass.”
Speaking on Feb. 5, Zumpfe said an arctic air mass similar to last weekend’s could move into the area the night of Feb. 8, although he acknowledged a degree of uncertainty in the forecast. Such a storm would mean the return of strong winds, lower temperatures and snow amounts roughly in the same range.
“Our pattern is going to cause more of these arctic and snow events in the next couple weeks,” he said. “There may be more of this to come.”
Skiers might rejoice over that forecast, while travelers and winter-weary residents won’t, but everybody should be happy about this tidbit: Western Montana’s snowpack is much higher than in neighboring states heading into spring and summer. Northwest Montana mountain ranges in particular are 120-135 percent of normal.
“As far as water storage goes, those are some pretty good numbers,” Zumpfe said.