GNFAC Avalanche Forecast for Sat Mar 13, 2021

Not the Current Forecast

Good Morning. This is Ian Hoyer with the Gallatin National Forest Avalanche Forecast on Saturday, March 13th at 7:00 a.m. Today’s forecast is sponsored by Grizzly Outfitters and Summit Motorsports and Ski-Doo. This forecast does not apply to operating ski areas.

Mountain Weather

We’ve got another beautiful spring day in store. There is no new snow this morning. Skies are clear, winds are light, and temperatures are in the teens and 20s F. Temperatures will rise around 5 degrees higher than yesterday, into the 30s and low 40s F. North and east winds will increase this afternoon, gusting up to 30 mph. The next chance for precipitation is Monday.

Snowpack and Avalanche Discussion

As temperatures warm and the snow melts in town, it’s a natural inclination to shift our focus towards spring and wet snow avalanches. But don’t forget, the lower snowpack on most slopes remains dry. The weak layers that formed last fall are still lurking down there (Teepee Basin video). While these weak layers haven’t gained much strength, without recent loading you are unlikely to trigger an avalanche on them. Use safe travel practices to minimize the consequences if you do: always carry rescue gear, go one at a time in avalanche terrain, and watch your partners from a safe spot (travel advice video).

Although temperatures will be a few degrees warmer than yesterday, increasing wind will help keep wet snow problems in check on most slopes. Still, be on the lookout for wet snow on sunny slopes as the day heats up, particularly lower elevation slopes protected from the wind. As crusts break down, if you’re sinking more than ankle deep into wet snow, it’s time to move off steep slopes before you trigger a wet slide. These slides will generally be small, but on isolated slopes where the snowpack is saturated, wet slides could gouge to the ground or break as wet slabs (Specimen creek video).

Yesterday, skiers in the northern Bridger Range stopped during their ascent, dug, and got quite unstable test results (ECTP13). They backed off their objective and headed back to the car. This is an appropriate mindset during Low danger. Making more ambitious goals is reasonable, but keep searching for signs of instability and be ready to back off if you find them. 

Large avalanches are unlikely and the avalanche danger LOW.


While conditions are generally stable in the mountains around Cooke City, there are some small and/or isolated concerns. Several small slab avalanches were reported after the last snowfall and while they will mostly have stabilized, you might still be able to trigger a similar slide (photo, photo). Triggering small loose wet avalanches will also be possible as the day warms up (photo). We’ve had reports of small sluffs running long distances over firm crusts.

The avalanche danger is rated LOW

If you get out, please send us your observations no matter how brief. You can submit them via our website, email (, phone (406-587-6984), or Instagram (#gnfacobs).


Upcoming Avalanche Education and Events

See our education calendar for an up-to-date list of all local classes. Here are a few select upcoming events and opportunities to check out:

March 20, 5:30 p.m., Snowpack Update for Bozeman Splitfest, online Link to Join HERE

March 24, 6 p.m., Free 1-Hour Avalanche Awareness, online Link to Join HERE

March 29, 6 p.m., Free 1-Hour Avalanche Awareness, online Link to Join HERE

The Last Word

The University of Nevada, Reno School of Medicine and Montana State University, are doing a brief survey to learn if, and how, use of the winter backcountry has changed due to the coronavirus pandemic.  The 5-minute survey is HERE.