Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Monday, March 11 at 7:30 a.m. Bridger Bowl in partnership with the Friends of the Avalanche Center sponsor today’s advisory. This advisory does not apply to operating ski areas.
Over the past 24 hours most areas picked up 1-2 inches of new snow with the exception the Bridger Range which has remained dry. This morning, temperatures are in the upper teens to mid-twenties F and winds are blowing 15-30 mph out of the WNW with gusts near Big Sky reaching into the 40s. Today, highs will climb into the upper 20s to low 30s and winds will continue to blow 15-30 mph out of the WNW. A weak weather system will move across the region producing valley rain and light mountain snow. Most areas will pick up and additional 1-2 inches with the excepting of Cooke City which will likely see 3-5 inches by tomorrow morning.
Bridger Range Madison Range Gallatin Range
Lionhead area near West Yellowstone Cooke City
Today, wind loaded slopes will be the primary avalanche concern. Yesterday, a skier was caught in a small slide near Naya Nuki in the northern Bridgers. This slide appears small and harmless; however, if the skier triggered this slide in high consequence terrain the outcome could have been different (photo). A skier outside of Cooke City also found wind loaded slopes to be the primary avalanche problem. He found south and east facing slopes to be the most loaded where a few natural avalanches were observed in alpine terrain (photo). A large natural avalanche was also observed on Fan Mountain near Big Sky. The crown was 2 feet deep and 3-400 feet wide. The slide was likely triggered by a cornice fall. This bulls eye data indicates that wind loaded slopes are willing and able to produce avalanches.
A secondary concern is a layer of facets buried 2-3 feet deep (video). This layer is most prevalent in areas with a shallow snowpack. Steep slopes – specifically those with thin, rocky margins will be susceptible to human triggered avalanches. Although it’s becoming increasingly difficult to trigger slides on these deeper layers, they continue to deserve respect. Evaluating snow and terrain carefully is a good way to stay out of trouble.
Today, wind loaded slopes and slopes steeper than 35 degrees have a MODERATE avalanche danger. Less steep, non-wind loaded slopes have a LOW avalanche danger. If snow and wind come in stronger than expected today – the avalanche danger could rise to CONSIDERABLE on steep, wind loaded slopes by this afternoon.
Doug will issue the next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations drop us a line at mtavalanche@gmail.com or call us at 587-6984.
Montana Ale Works Fundraiser Dinner
Tickets are on sale now to the 5th Annual Friends of the Avalanche Center Dinner and Wine Pairing on Wednesday, March 13th at 6:00 p.m. Call the host stand at 587-7700 to reserve your space. Tickets are $75 and all proceeds go to the Friends of the Avalanche Center. There are only 40 tickets available and this event sells out every year so get them while you can!