Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Saturday, February 27, at 7:15 AM. Today’s advisory is sponsored by Soda Butte Lodge and Katabatic Brewery. This advisory does not apply to operating ski areas.
This morning temperatures are in the upper 20s to low 30s F and winds are blowing 15-30 mph out of the W-SW with gusts around Hyalite and Big Sky breaking 40 mph. Today, gusty conditions will continue as a storm system moves into the area. Winds will continue to blow 15-30 mph out of the W-SW with stronger ridgetop gusts likey. Temperatures will remain warm with highs climbing into the mid to upper 30s F. Snow will develop over the mountains by late morning/early afternoon and will continue through the evening hours. By tomorrow morning, the mountains around Bozeman will likely see 2-4 inches while the southern mountains including Big Sky will pick up 3-5 inches.
Southern Madison Range Southern Gallatin Range
Lionhead area near West Yellowstone Cooke City
Over a week ago a well-developed layer of surface hoar got capped by 1-2 feet of snow. Widespread avalanche activity occurred immediately after this layer was buried. Over the past week there has been no new snow and avalanche activity has tapered off. However, this layer still exists 1-2 feet under the surface and continues to produce unstable conditions in specific areas (video).
On Thursday, a snowmobiler triggered and narrowly escaped being buried in a slide near West Yellowstone (photo). This was the last reported human trigged avalanche in our area. Although we didn’t trigger any slides yesterday - Alex, Karl and I experienced cracking and collapsing on east and north facing slopes at Bacon Rind in the southern Madison Range (video). These signs of instability were the result of surface hoar collapsing a foot under the surface (photo).
This layer has the potential to become more active under the weight of new and windblown snow. With multiple storms on the horizon, it’s likely the avalanche danger will increase. Pay close attention to changing conditions and evaluate the snowpack and terrain carefully.
Today, human triggered avalanches are possible and the avalanche danger is rated MODERATE.
Bridger Range Northern Madison Range
Northern Gallatin Range
The mountains near Big Sky and Bozeman have a mostly stable snowpack. Yesterday’s warm temps softened the snow surface, which refroze overnight. This is good for stability, but terrible for skiing and riding conditions. The main avalanche concern today will be new snow. This will only be a problem if today’s storm arrives earlier and stronger than expected. If so, wind slabs near the ridgelines will be the problem to look out for. If snow does not develop, conditions will remain stable and avalanches will be unlikely.
Today, generally safe avalanche conditions exist and the avalanche danger is rated LOW. The avalanche danger could rise to MODERATE on wind loaded slopes by this afternoon.
I will issue the next advisory tomorrow morning by 7:30 a.m. If you have any snowpack or avalanche observations to share, drop us a line at mtavalanche@gmail.com or leave a message at 587-6984.
EVENTS and AVALANCHE EDUCATION
A complete calendar of classes can be found HERE.
Bozeman: Wednesday, March 9, 6-7 p.m. 1-hr Avalanche Awareness, REI.