The Gallatin National Forest Avalanche Center has released a report on an avalanche that killed two snowmobilers on Monday, December 27, 2021.
The two snowmobilers were caught and killed in an avalanche on Scotch Bonnet Mountain, north of Cooke City.
A group of eight snowmobilers from Minnesota were on their second day of riding when two of their machines got stuck on the southeast face of Scotch Bonnet Mountain.
Two members of their group rode up to help them dig out and the avalanche was triggered soon after. It broke 4-5 feet deep, ran 300 feet wide and 500 feet vertical, and killed 2 riders, burying them under 4-5 feet of debris. Everyone had rescue equipment and they were recovered by their party. Park County Sheriff Search and Rescue brought the victims to town. The avalanche broke on a layer of facets 1.5 feet off the ground underneath a thick slab of wind drifted snow. The avalanche is classified SS-AMu-R2-D2.5-O.
The names of the two people who died have not yet been released.
Since Wednesday morning the mountains around Bozeman and Big Sky got 1-2” while the higher elevations outside West Yellowstone and Cooke City received 3-4”. Last night a westerly wind was blowing strong which loaded many slopes that would likely be triggered by a skier or snowmobiler.
The southern mountains including the area around West Yellowstone and Cooke City have a CONSIDERABLE danger on these slopes. In the mountains around Bozeman and Big Sky, it is still possible to trigger slides on these wind drifts and the danger is rated MODERATE. Furthermore, a new weak layer was discovered in the middle of the snowpack in the Bridger Range which could possibly be triggered as well.