AccuWeather
A windy May snowstorm that started Wednesday afternoon will continue to produce snow, high winds and cold conditions across the region this weekend, as a prolonged stretch of unseasonably cold weather continues across the region. Initially, the storm started as rain before it changed to snow across most of Montana Thursday. Farther south, showers and thunderstorms spread across the Sierra Nevada and the Four Corners region. Winter storm warnings and winter weather advisories were in effect early Friday morning across western Montana and northern Idaho, and the Montana Department of Transportation reported severe driving conditions on Route 3. While these warnings and advisories were no longer in place by Saturday morning, AccuWeather forecasters say one more round of wintry weather is still on the way. This radar image, taken early Friday morning, May 21, 2021, shows the snow and rain that was falling across south-central Canada and Montana. (AccuWeather) As of early Friday morning, Dupuyer, Montana, was one of the snowiest spots with 16 inches of fresh snow on the ground. Not far to the west at the nearby Spotted Eagle Mountain, 15 inches of new accumulation was measured. As of early Friday morning. (AccuWeather) This wintry storm comes days after a spell of summerlike warmth basked the region. Great Falls, Montana, reported a high of 83 F Monday, which turned to a chilly 39 F Thursday. Helena, Montana, rose to a steamy 86 F Monday, only to have temperatures plummet to the upper 30s Thursday. Widespread areas of 1-3 inches of snow have fallen with this storm, from outside Calgary, Alberta, to Regina, Saskatchewan, and southward through Montana into Idaho and northwestern Wyoming. Snow levels dipped to as low as 3,000 feet at times. "An AccuWeather Local StormMax™ of 48 inches is expected with this storm over the higher elevations of west-central Montana," said AccuWeather Senior Meteorologist Alex Sosnowski. Here's another round of #snow pics from various webcams across western #Montana. #MTwx pic.twitter.com/Ub1vsqmWby— NWS Missoula (@NWSMissoula) May 20, 2021 While Montana and the northern Rockies are no stranger to heavy May snowfall, the average date of the last measurable snow in Great Falls is May 10, according to Sosnowski. The city received a total of 5.1 inches of snow from Thursday to Friday of this week. CLICK HERE FOR THE FREE ACCUWEATHER APP The above image shows Greenough Hill on Route 22 in Montana, with trees and non-paved surfaces covered in snow on Thursday morning, May 20 (Photo/MontanaDOT) "The storm could join the ranks of the top 10 greatest impact snowfalls for the region," said Sosnowski. Spring snowstorms are usually a problem as leaves start to grow on the trees at low and intermediate elevations. Large amounts of snow can put pressure on fully-fledged tree branches, increasing the likelihood that branches will break and knock out power across the area. This could turn dangerous with such cold temperatures funneling through the area and heating demands high. High temperatures in Montana at the end of the week will be more than 30 degrees lower than normal in some cases, according to AccuWeather Meteorologists. On the southern side of the massive storm, strong winds caused concerns with gusts over 70 mph in some areas, including an 81-mph gust at Weldon, California. Red flag warnings are in effect from the deserts of Southern California to Utah to southeastern Arizona through Saturday. These winds will produce very high fire danger according to AccuWeather meteorologists. Nearly 60% of both Utah and Arizona are under exceptional drought, according to the United States Drought Monitor. So far this May, Flagstaff, Arizona, has only received 7% of average rainfall. Lack of rainfall means dry vegetation will catch on fire easily, and high winds allow any sparks and fires to spread quickly. This first, far-reaching storm is forecast to end by Saturday, but forecasters say the Northwest isn't yet out of the woods in terms of snow. "Yet another round of snow will be in store for the northern Rockies late this weekend," said AccuWeather Meteorologist Isaac Longley. Another storm system ejecting out of the Southwest will bring periods of snow to the mountains of western Montana as well as western Wyoming and Idaho from Saturday night through Sunday. Forecasters expect most of the lower elevation towns to be spared from this next storm's snow, but snow is likely to fall in the mountains and at higher attitudes. "While the heaviest snow with this next round will be confined to the higher elevations, we can still see accumulating snow down to 5,000 in some spots, which may affect travel at times," Longley said. An additional foot or more of snow will be possible in the highest terrain with several inches likely at lower elevations. Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier, Spectrum, FuboTV, Philo, and Verizon Fios.
