This is Ian Hoyer with the avalanche forecast for Friday, December 13th at 7:00 am. This information is sponsored by the Bozeman Ice Festival, Bridger Bowl, and Ride Rasmussen Style. This forecast does not apply to operating ski areas.
There is at most a dusting of new snow. Temperatures are in the teens and 20s. Winds have mostly been 10-20 mph out of the south and west, with gusts of 25-35 mph. Except in Hyalite, where there were gusts up to 50 mph overnight.
Today, high temperatures will be in the 20s F. Skies will be sunny around Bozeman and Big Sky. Clouds will increase in southern areas, with light snow starting in Island Park.
Tonight, 1-3” of snow will fall in Island Park with little or none elsewhere.
Snow will spread further north tomorrow and tomorrow night, still favoring the Island Park area.
The primary avalanche concern today is wind drifts built from snow that fell earlier in the week. Winds picked up again last night (particularly in Hyalite) so there may be some new, fresh and unstable drifts today. Steer around these drifts to keep things simple and avoid triggering a Wind Slab avalanche. If you’re going to cross a steep slope with a cohesive wind drift, watch out for cracking, which is a clear sign that the drift is ready to avalanche.
Underneath this week’s snow, in many places, there is weak snow that formed over the preceding ten days of high pressure (Blackmore video, Cooke City photo). We haven’t had any reports of Persistent Slab avalanches yet, but we’ll be on alert as it starts to snow again.
For today, human triggered avalanches are possible and the avalanche danger is MODERATE.
With less recent snowfall, avalanche concerns are more isolated around Island Park and West Yellowstone. A couple inches of snow that fell earlier in the week capped weak layers, but there generally isn’t enough of a slab above them to get an avalanche (Island Park video). Keep an eye out in case you do find a deeper drift where an avalanche might be possible.
The avalanche danger is LOW.
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar
Today, Friday, Dec 13, attend a free motorized avalanche awareness talk at Basecamp Gallatin in Four Corners from 6:30 to 8 pm from Six Points Avalanche Education.
This Friday, Saturday, or Sunday - Take 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 79% of the way to our goal. Please consider making even a small donation HERE or via Venmo