Good morning. This is Mark Staples with the Gallatin National Forest Avalanche Forecast on Wednesday, December 4th at 7:00 am. This information is sponsored by the Upper Yellowstone Snowmobile Club, Cooke City Motorsports, and Beartooth Powder Guides. This forecast does not apply to operating ski areas.
Weather this morning and for today is generally a repeat of yesterday. Temperatures this morning range from the mid 20s to low 30s F. Winds from the NW are blowing 10-15 mph gusting to 30 mph.
Today high temperatures will range from low 30s to low 40s F depending on elevation. Winds will continue from the NW but will be decreasing. Looking ahead, the ridge of high pressure creating dry and warm conditions breaks down this weekend and snowfall should return on Sunday.
Snow depths range from about 15 to 30 inches, and recent dry, warm weather has created highly variable snow conditions. The only recent avalanches have been wet loose avalanches on slopes getting direct sunshine and generally having exposed rocks that add extra heat to the snow. Also, we’re tracking the condition of the snow surface which is weakening on many slopes.
Wet loose avalanches have become less likely because the snow has gone through several melt-freeze cycles. Ice climbers watch out if you’re in a long gully. Even if you’re in the shade, pay attention to heating of the snow on slopes above you because even a very small avalanche can sweep you off your feet.
Avalanches involving dry snow are unlikely, but there are some weak layers of faceted snow lurking in the snowpack. They seem to be more prevalent from Big Sky and south towards West Yellowstone. Ian and Dave found some in the Taylor Fork area of the Southern Madison Range yesterday but still felt avalanches were unlikely. They would probably require an old wind slab on top to get an avalanche today.
Today the avalanche danger is LOW. It’s still early in the season and there’s a lot of variability as well as a lot of buried rocks and stumps to hit.
The snowpack around Cooke City is similar to the rest of the forecast area with one glaring exception that shouldn’t be ignored. An experienced skier south of town on Monday triggered several large collapses on east and west aspects.. Collapsing makes an audible whoopfing sound and is just like triggering an avalanche except it happens on flatter terrain, so the snow doesn’t slide downhill. I found buried facets on south and northeast aspects yesterday.
Persistent slab avalanches are the main concern near Cooke City. Despite a lack of avalanche activity, recent snowfall, or recent wind loading, the snowpack is guilty until proven innocent. For this reason the danger is MODERATE.
Ice climbers should also watch out for wet loose avalanches and look for heating of the snow especially in places like Barronette Peak in long southeast facing gullies.
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar
Tuesday, December 10, 9 a.m.-3 p.m., West Yellowstone Avalanche Fundamentals: Motorized Guide Cert Course, Pre-registration required.
For an intro class with a field day, Register for our Avalanche Fundamentals course.
Friends of the Avalanche Center: Fall Fundraiser!
We’re still counting on your support and the online Fall Powder Blast fundraiser is 79% of the way to our goal. Please consider making even a small donation HERE or via Venmo