GNFAC Avalanche Forecast for Sun Mar 14, 2021

Not the Current Forecast

Good Morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Sunday, March 14th at 7:15 a.m. Today’s forecast is sponsored by Uphill Pursuits and Knoff Group Real Estate. This forecast does not apply to operating ski areas.

Mountain Weather

Since yesterday morning wind has been east-northeast at 5-15 mph with gusts to 30 mph, and in the Bridger Range speeds were 20-30 mph with gusts of 40-50 mph. This morning there is no new snow and temperatures are low to mid-20s F. Today, skies will be mostly clear with temperatures reaching high 30s to low 40s F. Wind will be east-southeast at 5-15 mph with higher speeds continuing in the Bridgers. The next chance for snow is late tomorrow and Tuesday.

Snowpack and Avalanche Discussion

In the Bridger Range, strong east wind since yesterday afternoon drifted snow from earlier this week into fresh slabs. Watch out for these drifts in unusual locations due to the less common wind direction. Although not widespread, these wind slabs are possible to trigger and could be large enough to injure or bury a person. Large avalanches breaking on weak snow at the ground and small wet loose slides are unlikely, but should be kept in mind if you are riding steep slopes (more on those hazards below). Today, avalanche danger is MODERATE on wind-loaded slopes, and LOW on all other slopes.

In the mountains near Bozeman, Big Sky and West Yellowstone there is weak, sugary snow at the base of the snowpack (Doug’s video from Teepee Basin last week shows this poor snowpack structure). It is unlikely to trigger an avalanche on this layer right now, but the result would have huge consequences. Carefully assess the snowpack and choose terrain to minimize the chances of encountering this deep slab hazard.

Another warm, sunny day creates a chance for small wet loose avalanches on slopes that receive direct sun. These slopes have a crust on the surface that formed from previous days of sunny, warm weather. Anticipate the possibility of wet loose avalanches later in the day, and avoid being underneath or on steep, sunny slopes if the crust has melted and the surface is wet. Wet slides will generally be small, but on isolated slopes where the snowpack is saturated, wet slides could gouge to the ground (Specimen creek video). Today, large avalanches are unlikely and the avalanche danger is LOW.

Yesterday near Abiathar Peak west of Cooke City, skiers were nearly hit by a large falling cornice while they were hiking up a steep chute (details). Most slopes are stable and avalanches are unlikely, but isolated hazards exist. These hazards may be small or unlikely, but are potentially deadly if you are in the wrong terrain. Snow that fell earlier this week created small slabs, and we saw loose snow avalanches that ran far on the firm crust underneath (photo, photo, video). Today, be on the lookout for small wind slabs formed by recent moderate east wind, and loose snow slides and cornice falls as temperatures warm above freezing (photo). Today, isolated hazards exist, and 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 (mtavalanche@gmail.com), 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.