GNFAC Avalanche Forecast for Sun Feb 6, 2022
Not the Current Forecast

Good morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Sunday, February 6th, at 7:00 a.m. This forecast does not apply to operating ski areas.

Mountain Weather

Since yesterday morning the mountains got 7" of snow near Cooke City, 4" in Hyalite, 1-2" near West Yellowstone, and a trace to 1" in the Bridger Range and Big Sky. Yesterday, northwest wind was 20-30 mph with gusts to 55 mph. This morning, wind has decreased to 5-15 mph with gusts to 25 mph, and temperatures are single digits to teens F. Today, skies will be mostly clear with temperatures reaching 20s to low 30s F, and west-northwest wind will average 5-15 mph with gusts to 25 mph. No snow is expected for a few days.

Snowpack and Avalanche Discussion

Cooke City

Yesterday's storm gifted Cooke City with 10" of low-density snow (0.6" of snow water equivalent), with possibly more in higher areas. This new snow adds weight above weak layers that are now buried 18-24" deep (photo). Two days ago, these weak layers produced small skier triggered and natural avalanches (photo and details, details), and a skier triggered a large collapse of the snowpack on a low angle slope (details). Today avalanches are easy to trigger and will be large enough to bury or injure a person. Be extra cautious of steep slopes, even if you don't see obvious signs of instability. The snowpack needs time to be trusted with this new load of snow. Plan to avoid travel on and underneath slopes steeper than 30 degrees. Dangerous avalanche conditions exist and the avalanche danger is CONSIDERABLE.

Bridger RangeMadison RangeSouthern Gallatin Lionhead Range

Near West Yellowstone, Big Sky, and in the Bridger Range avalanches are unlikely or will be small. These areas got 5-10" of snow earlier this week which was drifted into slabs that might remain unstable in isolated areas. The last couple days wind was moderate to strong, but had minimal snow left to blow into drifts, and today wind has decreased to light with a few moderate gusts. Recently formed drifts have become generally stable. If you travel in steep terrain stay alert for areas of isolated instability, and carefully evaluate the snowpack for wind-loading and buried weak layers. Large avalanches are unlikely and the avalanche danger is LOW near West Yellowstone, Big Sky and the Bridger Range.

Lionhead Bottom Line: Last night's minor snowfall around Big Sky and Hyalite will not affect the general stable conditions we are finding in the mountains from Bozeman to West Yellowstone. Even with a stable snowpack we have to keep up our safety rituals. Just like buckling a seat-belt for a short drive, we need to always carry our rescue gear (beacon, shovel and probe) and literally only expose one person at a time in avalanche terrain.