GNFAC Avalanche Forecast for Sat Feb 1, 2025
This is Ian Hoyer with the avalanche forecast for Saturday, February 1st, at 7:00 a.m. sponsored by Spark R&D and Klim. This forecast does not apply to operating ski areas.
New snow totals this morning are:
12” of low density snow near Cooke City
4-5” around West Yellowstone, Island Park and Big Sky
Trace-2” near Bozeman
Winds have been strong out of the west, blowing steadily at 20-30 mph with gusts as high as 55 mph. Temperatures are in the teens and 20s F this morning.
Another pulse of snow this afternoon will bring 1-3” to much of the advisory area by nightfall, favoring the southern regions. By tomorrow morning, 4-8” will accumulate in Island Park and Cooke City, with 1-3” elsewhere. High temperatures will be in the 20s F and it’s going to stay windy - blowing 20-30 mph out of the west with stronger gusts.
Snow continues tomorrow and into the workweek.
Wind Slab avalanches on wind loaded slopes are the primary concern today. A foot of new snow and perfect drifting winds means these drifts of new snow could easily be 2-4 ft deep.
The new snow is piling up on a variety of snow surfaces - some weak, some not - so check to see how well the new snow has bonded to the old snow surface before getting onto slopes steeper than 30 degrees (video). Conditions could be quite touchy on slopes with weak snow underneath the fresh drifts.
The low density snow is unlikely to form much of a slab without wind effect, but remarkably soft slabs can break if they’re sitting on surface hoar (a weak layer which we’ve had reports of - observation), so don’t entirely let your guard down on non-windloaded slopes.
Human triggered avalanches are likely and the avalanche danger is CONSIDERABLE on wind-loaded slopes. On all other slopes, the avalanche danger is MODERATE.
Wind Slab avalanches are also the primary concern in the Madison and Gallatin Ranges, Lionhead area, and mountains around Island Park. Fresh wind slabs were already breaking yesterday, before it started snowing (Mt. Blackmore observation). Expect more of the same today, but they could be both deeper and wider. The deeper the drifts of new snow, the more dangerous conditions will be. A short, intense period of snowfall this afternoon may rapidly form new, unstable drifts.
Weak snow has been reported on the old snow surface across the area (observation, observation). High winds may have blown away some of that weak snow before the new snow started falling, but probably not all of it. So if you find a wind drift more than around 6” deep, check to see what it’s sitting on top of. Cracks shooting out in front of you are bullseye data that you’ve found an unstable drift.
Human triggered avalanches are possible and the avalanche danger is MODERATE.
A dusting of new snow in the Bridger Range won’t do much to increase the hazard today. Watch out for thin drifts of new snow if you’re riding in terrain where even a small slide would have big consequences (above rocks, cliffs, etc.) and stick with good travel practices (wearing rescue gear, having a partner watching from a safe spot) in case you get unlucky and manage to trigger a bigger slide in an older winddrift.
Conditions are generally safe and the avalanche danger is LOW.
KING AND QUEEN OF THE RIDGE
Join us for the King & Queen of the Ridge TODAY at Bridger Bowl! Registration for the event has closed, but come join us at the top of the Bridger lift to cheer on the participants! You can still donate here to support the hikers and your avalanche center!
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar
February 6, 6-8 p.m. & February 8, 10 a.m - 2 p.m. Companion Rescue Clinic. Evening lecture at REI in Bozeman. Field session at History Rock. Details and signup here.
February 20, 4-7 p.m. Beacon BBQ at Uphill Pursuits in Bozeman. Come try out different brands of avalanche transceivers (or practice with your own!) with coaching from Friends of GNFAC instructors and free hotdogs.
Every weekend in Cooke City: Friday at The Antlers at 7 p.m., Free Avalanche Awareness and Current Conditions talk, and Saturday from 10 a.m.-2 p.m. at Round Lake Warming Hut, Free Rescue Practice.
Thank you for sharing observations. Please let us know about avalanches, weather or signs of instability via the form on our website, or you can email us at mtavalanche@gmail.com, or call the office phone at 406-587-6984.