Good morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Sunday, January 7th at 7:15 a.m. This information is sponsored by Alpine Orthopedics & Sports Medicine, Community Food Co-op and Knoff Group Real Estate. This forecast does not apply to operating ski areas.
At 5 a.m. the mountains near West Yellowstone and Island Park have 6-9” of low density new snow with 1-2” near Bozeman, Big Sky and Cooke City. Yesterday wind was out of the southwest at 15-20 mph with gusts of 35-45 mph, and today wind has decreased to 5-15 mph. Temperatures are single digits to teens F this morning. Today temperatures will reach teens to low 20s F and wind will be from northwest-northeast at 5-15 mph. Snow showers today could drop 3-5” near Bozeman with 1-3” elsewhere.
All Regions
Today avalanches can be triggered on wind-loaded slopes where the new snow was drifted into thicker slabs. These slabs are 4-12” deep and sitting on a very weak snowpack which is causing them to break easily and propagate wide. Watch for signs of recent wind-loading such as cornices, rounded smooth pillows of snow and snow surfaces with wavy textures. Be extra cautious of slopes that appear wind-loaded. Cracking across the surface of the snowpack is a sign you have found an unstable drift that will slide on steep slopes.
Additionally, the weak snowpack is contributing to large dry loose avalanches on long, sustained steep slopes (photo from Buck Ridge, photo from Beehive, photo from Cooke). These ”facet sloughs” carry plenty of force to knock you over as they entrain almost the entire snowpack. Yesterday at Buck Ridge we saw a fresh natural avalanche and easily intentionally triggered a few shallow wind slabs and long running facet sloughs (video, wind slab photos, natural avalanche photos).
Near West Yellowstone and Island Park, where up to 9” of low density snow fell (0.3” of snow water equivalent), larger avalanches are possible. In general, current avalanche concerns are small and easy to identify, but they point to a very unstable snowpack. The weak snowpack could cause avalanches to break above you, wider or larger than expected. Any size slide can get you into trouble if it carries you into trees, over cliffs or rocks, or piles up deeper in a confined gully.
Before crossing steep slopes, carefully assess the snowpack for signs of wind-loading and consider the consequences of an avalanche. Today the avalanche danger is MODERATE throughout the forecast area.
If you venture out, please fill an observation form. It does not need to be technical. Did you see any avalanches? How much snow is on the ground? Was the wind moving snow? Simple observations are incredibly valuable. You can also contact us via email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.
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.
We offer Avalanche Fundamentals with Field Session courses targeted towards non-motorized travelers in January and one geared towards motorized users. Sign up early before they fill up.
King & Queen 2024, 3 February 2024. Form a team or sign up individually to hike laps on the Bridger Bowl ridge to fundraise for the Friends of the Avalanche Center.
Loss in the Outdoors is a support group for those affected by loss and grief related to outdoor pursuits. Check out the link for more information.
Here’s a quick read, The Invisible Hands of Avalanche Work, an interview with GNFAC forecaster, Doug Chabot.