Montana Public Radio

'Unprecedented' Storm System Moving Into Montana

Oct 22, 2020

Montana is about to get a blast of wintery weather the likes of which have never been recorded in mid-October. Forecasters say the powerful storm could have a major impact on early weekend travel and eventually usher bitterly cold Arctic air into the region by Sunday morning.

The early season winter storm is on track to roll through Montana starting Friday afternoon. The National Weather Service describes it as a ‘high impact’ weather event.

“This storm system is unprecedented," Meteorologist Trent Smith says.

The powerful Arctic storm is going to play out in three separate acts.

Act 1 begins Friday afternoon. That’s when the front pushes into northwest Montana. Local snowfall amounts of 2-4 inches are possible, with 4-8 inches in the Mission Valley. Higher amounts are possible in the mountains.

"And then Friday evening that snow really starts shifting southward – more over west-central Montana," Smith says. "Missoula is anticipated to get upwards of 4 inches of snow. So, a big concern is that evening rush hour and pretty much the whole I-90 corridor from Lookout Pass down to Garrison Junction."

More snow is likely late Friday night. Three more inches could accumulate in Missoula for a possible total of 6-8 inches. Great Falls might get a foot, with 11 inches in Billings, 7 inches in Browning and up to 8 inches in Miles City.

The system’s second act – the wind – arrives in northwest Montana Friday night and spreads south and east throughout the evening. Some gusts could reach 50 miles per hour, creating blizzard-like conditions.

"There are still plenty of trees out there with leaves that are well attached. So, any hefty snow on that could actually cause some tree branches to break, causing power lines to fall down."

The system’s third and final act? Bitterly cold temperatures Sunday and Monday mornings.

According to the National Weather Service many locations could see lows that would even be records for the first week of November let alone October 25-26th.

The potential exists for double-digit negative temperatures along the Continental Divide, and single-digit negative temperatures for the rest of Western Montana.

We’ll see a return to warmer, far-more seasonable daytime highs in the 40s by Tuesday.