Below: A quick glimpse at the projected snowfall map through 6AM (MTN) on Sunday morning. SW Montana, east of the Continental Divide looks to get walloped by this complex storm system. 

West of the Continental Divide:

Friday: Webcams around the region indicate widespread light snowfall as of 9AM Friday morning with 4” new at Snowbowl, 3” Lost Trail (LT) and Lookout Pass, and 1” at Disco and Whitefish. A Pacific low-pressure circulation and associated cold front will continue to bring widespread light snowfall across the region through Friday night. The majority of the snowfall looks to occur across the mountains along and south of I-90 with additional daytime accumulations of 3 – 6” at Snowbowl, LT, Disco, and Lookout. Clouds with snow showers to the north with another 1 – 3” possible at Whitefish and Blacktail by days end. Cooler on Friday with mountain top highs ranging from 25F at Whitefish to 28F at Lookout and Lost Trail. Breezy west winds, with ridgetop gusts to 25 mph.  

Saturday: Friday night weak disturbances continue to move through the region along and south of the I-90 corridor with overnight accumulations of 1 – 4” at Lookout, LT, Snowbowl and Disco. With a deep trough of low-pressure encamped just south of the region, look for a continuation of snow shower and snow band (across west central areas) development on Saturday bringing light accumulations of 1 – 3” for the aforementioned ski areas. Generally cloudy and unsettled across the NW where Whitefish and Blacktail could see trace amounts on Saturday. Temps will be running about 10 degrees colder than seasonal with mountain top highs in the upper teens to middle 20’s across the region. Light winds expected. 

Sunday: Saturday night will see a continuation of periodic snow showers with LT, Snowbowl, and Disco best positioned for 2 – 4” overnight. After a slight morning lull, snowfall begins again during the afternoon hours on Sunday (again, along and south of I-90) as a second punch of moisture wraps around a closed low developing over eastern Idaho. Add another 3 – 6” through Sunday night for Disco, with 2 – 5” possible at LT and Snowbowl. To the north, Blacktail and Whitefish will see clouds and periods of afternoon snow showers on Sunday with a slight chance of an inch or two. Mountain top high temps in the upper 20’s across the region. Light west winds. 

Monday & Tuesday: While still under a weakening trough of low-pressure look for a couple of mainly dry but mostly cloudy days with chances of afternoon graupel showers. Some light accumulations are possible under these hit and miss convective snow showers. Temps continue to be below average with upper mountain highs in the upper 20’s to low 30’s.    

East of the Continental Divide: 

Below: Big Sky under light snowfall Friday morning. More, much much more, is on the way.

Friday: Attention now focuses on the ‘eastside’ where a blanket of Winter Storm Warnings and Snow Advisories cover the region. Snowfall has begun at Bridger and Big Sky with 3” as of 9AM Friday. A NW flow will deliver moisture from a Pacific shortwave and associated cold front on Friday bringing periods of heavy snow that look to continue through Friday night. SW Montana is the place you want to be with Red Lodge in the crosshairs of the moisture feed where 10 – 15” is likely during the overnight hours Friday. Bridger Bowl and Big Sky will see a full-on storm day on Friday with an additional 5 – 10” falling through Friday night. Bridger Bowl could surpass these numbers as upslope conditions are looking more likely. Could a ‘Bridger Cloud’ be in the offering? Elsewhere across the region, generally 1 – 4” look likely through Friday night. Quite chilly on Friday behind the cold front with afternoon highs at 8000’ of 20 – 25F. Light to moderate W/SW winds keep things brisk across alpine areas. 

Saturday:  Winter Storm Warnings continue across SW Montana through the 24-hour period. As the shortwave low moves to the south/southeast through Idaho it will continue to pump moisture into SW Montana. Persistent periods of moderate to heavy snow will continue through the day on Saturday at Red Lodger where another 8 – 12” look to fall by 4PM. Big Sky and Bridger will also see significant snowfall in the 4 – 8” range through the day. Elsewhere across the region, periods of light snow with accumulations of 1 – 4”. Temps will remain 10- 15 degrees below seasonal average with 8000’ high temps in the mid to upper teens. Light to moderate NW winds. 
  
Sunday: Winter Storm Warnings across SW Montana remain in effect for the 24-hour period. As a closed low develops over southern Idaho, a second but slightly weaker punch of the weekend storm will arrive Saturday night bringing a reinforcement of light to moderate snowfall that looks to last through the day on Sunday. Overnight accumulations of 2 – 5” at Red Lodge, Bridger Bowl and Big Sky are likely. Periods of more widespread light to moderate snow continue Sunday across the region adding another 4 – 8” at Red Lodge, with 2 – 4” at Big Sky, Bridger, Maverick, Great Divide, Teton Pass, and Showdown. Continued chilly with highs at 8000’ in the upper teens. Light north winds.  

Monday & Tuesday: The trough of low-pressure that’s been draped across the PNW and Northern Rockies over the weekend will weaken on Monday bringing a mostly cloudy couple of days with daily chances of an isolated snow shower. Continued cold on Monday with 8000’ high temps in the mid to upper teens. Slightly warmer on Tuesday under sporadic sunny spells with highs reaching into the low 20’s at 8000’. 

Wednesday, March 29th through Friday, March 31st 

Another deep Pacific storm is still favored by most models to ride down the West Coast and plow into California towards the middle of next week. What this large circulation will do is create a moist SW flow aloft that looks to transport some moisture up and into the Northern Rockies. Once again, SW Montana looks to be in the storm track as some moderate accumulations look likely Wednesday through Friday of next week. Continued below seasonal temps look likely through the week. 

Below: The Euro Deterministic extended forecast map Tuesday 3/28 through midnight Friday 3/31. Follow the Pacific Storm into California, this will be responsible for a SW flow of moisture to possibly effect the Northern Rockies in the middle of next week.

 

Thanks for tuning in. Storm update on Sunday 3/26.  

Powder Out – 

Bob