Good morning. This is Dave Zinn with the Gallatin National Forest Avalanche Forecast on Tuesday, January 10th at 7:15 a.m. This information is sponsored by the Yellowstone Club Community Foundation and Gallatin County Sheriff Search and Rescue. This forecast does not apply to operating ski areas.
This morning, temperatures are in the upper teens to low 20s F with 10 to 20 mph wind from the west to southwest. The mountains around Cooke City, West Yellowstone, and Big Sky received 3-4” of new snow, with 1-2” near Bozeman. Today, high temperatures will be around 30 degrees F with light winds blowing 5-10 mph from the west to southwest. We may see another inch of snow this morning. The mountains around West Yellowstone will get another 2-4” of snow tonight.
The southern ranges of the advisory area have received 7-9” of new snow in the last 48 hours. With snowfall and wind decreasing this morning, I do not expect to see natural avalanches during the day, one of the thresholds for considerable danger. However, we are on edge with large, human-triggered avalanches being a distinct possibility. In the last three days near Cooke City, a skier was caught and carried in an avalanche in the Sheep Creek drainage, snowmobilers triggered avalanches near Chimney Rock on Henderson Mountain and near Lulu Pass (photo and details, avalanche activity list). Ten days ago, there was a tragic avalanche fatality on Crown Butte (accident report, video).
Avalanches breaking below the new snow and recent drifts are most likely, but weak layers buried throughout the snowpack, including sugary snow near the ground, make possible a full spectrum of avalanches from relatively small to very large. Watch my video from the Taylor Fork in which I point out these layers.
The avalanche activity list is an excellent place to start when considering terrain choices today. Avoid slopes steeper than 30 degrees if you observe recent avalanche activity, evidence of drifting, cracks shooting from the skis or board, whumphs, or get unstable test results.
The avalanche danger is MODERATE.
Yesterday, the northern portions of the advisory area received 1-3” of new snow and experienced strong winds. Avalanches failing within recent drifts of snow and on persistent weak layers buried deeper in the snowpack are possible. On Sunday, a snowmobiler triggered a small avalanche on a wind-loaded slope in First Yellowmule at Buck Ridge (details) and a snowboarder remotely triggered an avalanche in the backcountry outside of Big Sky Resort from 20 feet away (details). On Saturday, an avalanche caught and partially buried a snowboarder on a wind-loaded slope at Buck Ridge (details and photo). Skiers in the northern Bridger Range saw a recent natural avalanche that failed deep within the snowpack (photo). A near miss on Saddle Peak in the Bridger Range that broke 550 feet wide and almost 2 feet deep on a buried weak layer rounds out the avalanche activity from the last four days (photos and details).
As Alex and I suggested in our video from the Bridger Range Sunday, perform a careful snowpack assessment looking for instability related to buried weak layers before considering going into avalanche terrain. Choose slopes without terrain traps like cliffs, trees or rocks and follow safe travel protocols.
The avalanche danger is MODERATE.
Please share avalanche, snowpack or weather observations via our website, email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).
The Centennial Range received 7” of snow in the last 48 hours. Avalanches are most likely to break below the new and wind-drifted snow but could break deeper in the snowpack on buried weak layers. Slopes with drifts from yesterday’s strong winds are the most suspect. Evaluate the snow and terrain carefully to identify concerns related to wind-drifted snow and buried weak layers.
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.
TONIGHT, Tuesday, January 10th, 6PM, Women’s Specific Avalanche Awareness + Beacon Practice at Story Mill Park in Bozeman. Free.
Thursday, Jan 12th, 6:30 PM, 1hr avalanche awareness for mechanized users at BSCO BASE in Big Sky. Free.
Every Saturday, 10 a.m. - 2:00 p.m. Avalanche Rescue Training, drop in for any amount of time. Round Lake Warming Hut, Cooke City. Free.
Loss in the Outdoors, is a support group for those who have been affected by grief and loss related to outdoor pursuits. Check out the link for more information.
On Saturday in Colorado, two snowmobilers were caught, buried, and killed in a large avalanche on the east face of Mount Epworth, about 6 miles east of Winter Park. Grand County Sheriff's Deputies and search and rescue were unable to locate the second rider before dark, but found the second rider deceased yesterday. (Preliminary report).