Good morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Tuesday, December 3rd at 7:00 am. This information is sponsored by Knoff Group Real Estate, Werner Wealth Management (Advisors with DA Davidson) and Gallatin Valley Snowmobile Association. This forecast does not apply to operating ski areas.
At 4am temperatures are near or above freezing (30-34 F) at ridgeline weather stations and mid-20s F in most valleys with 46 F at the base of Bridger, and mids-20s F in Cooke City. Wind has been moderate out of the west at 10-15 mph with gusts of 20-35 mph. Today, skies will be clear with temperatures in the mid-40s near Bozeman and Big Sky and high 30s F near West Yellowstone, Island Park and Cooke City. Wind will be out of the west at 5-15 mph with a few moderate gusts. The rest of the week looks similar with a slight cooling trend, and the next chance for snow is this weekend.
Near Bozeman, Big Sky, West Yellowstone and Island Park Wet loose avalanches are the main avalanche concern today with temperatures at high elevations starting near or above freezing this morning. Yesterday, Dave and Mark skied at Bridger and looked at a wet loose avalanche that ran naturally on Sunday afternoon (video and photos, photo and obs. 2), and at Big Sky the ski patrol reported wet loose avalanches involving the top 3-4” of snow.
Wet loose slides may be relatively small, but should not be underestimated. They can easily knock over or carry a person, and would be especially dangerous if they pushed you over rocks, cliffs or piled deeply in a confined terrain feature. Ice Climbers should be particularly aware of the potential of wet loose slides starting naturally above climbs. Regardless of your activity, minimize or avoid spending time on and below steep slopes that receive direct sunlight.
On slopes where the snow is dry avalanches are unlikely. In isolated areas you might encounter an old drift of snow sitting on weak, sugary facets. Continue to assess the snowpack stability, and consider the consequences of even a small slide (Dave’s video from Beehive). The most recent avalanche activity involving dry snow occurred on Friday on Mt. Blackmore (details and photo) and in Beehive Basin (details), and snow rangers reported a couple old wind slabs on Buck Ridge yesterday (observation).
The avalanche danger is MODERATE for the possibility of wet loose avalanches.
In Cooke City wind slab avalanches are the primary avalanche problem. New snow from early in the weekend was drifted into fresh slabs that remain possible for a person to trigger. Avoid fresh drifts on steep slopes and look for signs of instability, including shooting cracks and recent avalanches. We have not had reports of avalanches breaking on persistent weak layers, and observations have shown a lack of widespread instability, but you should dig down to look for buried weak layers and test stability of recently drifted snow if you plan to ride or ski on steep slopes.
Temperatures will reach above freezing under clear skies which makes wet loose avalanches a concern on slopes that receive direct sunlight. A sticky or wet snow surface is a sign these are possible. Find shady slopes to ski or ride. Ice Climbers should pay attention to the potential for avalanches to start naturally in terrain above them. A small slide can easily be deadly if it knocks you off a climb.
The avalanche danger is rated MODERATE.
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 77% of the way to our goal. Please consider making even a small donation HERE or via Venmo
Bridger Bowl has backcountry conditions, and there are no ski patrol services. While they set up for the season, please steer clear of snowmaking equipment, chairlifts, and snowmobiles and respect posted signage.