GNFAC Avalanche Forecast for Tue Feb 22, 2022

Not the Current Forecast

Good morning. This is Dave Zinn with the Gallatin National Forest Avalanche Forecast on Tuesday, February 22nd, at 7:15 a.m. This information is sponsored by Highline Partners and World Boards. This forecast does not apply to operating ski areas.

AVALANCHE FATALITY IN COOKE CITY

Sadly, a snowbiker died in an avalanche near Miller Mountain in the Sheep Creek drainage north of Cooke City on Saturday. The accident site video is available along with preliminary information and photos. We will publish a full accident report soon. Our condolences go out to the family and friends of the rider.

Mountain Weather

Temperatures this morning range from -12 to -25 degrees F with 5-10 mph winds from the east to northeast and except in the Bridger Range where they are gusting to 60 mph. Lone Peak received 2” of new snow. Today, strong winds will continue to blow 25 mph from the east in the Bridger Range and 5-10 mph elsewhere. Temperatures will be in the negative to positive single digits F. Light flurries will bring a trace of new snow.

Snowpack and Avalanche Discussion

Strong east winds in the Bridger Range are transporting this weekend’s snow into unstable slabs where human-triggered avalanches are likely. Wind-loaded slopes will be atypical due to the easterly wind direction. Yesterday, Alex and Ian saw many loose snow avalanches that picked up enough volume to be dangerous in technical terrain (photo) warning that locations with drifted snow would become more unstable (video). On slopes unaffected by the wind and lacking recent drifts, human-triggered avalanches are possible. Avoid wind-loaded slopes and dig to test the stability of the new snow and buried weak layers before getting into avalanche terrain. The danger is CONSIDERABLE on wind-loaded slopes and MODERATE on all others.

Frigid temperatures narrow your margin for error by exacerbating minor incidents and adding risk for rescue teams. Make conservative travel plans for the day.

In the last week in Cooke City, 18” of new snow loaded weak layers buried 18-30” deep and resulted in dangerous avalanche conditions. Sadly, a fatal avalanche occurred in the Sheep Creek drainage Saturday (video, photos and preliminary details). Yesterday, a rider triggered an avalanche that broke 200’ wide, ran the entire 50’ vertical available and piled snow deeply at the base of the small hill (photo and details) and a group of riders saw a 700’ wide avalanche on the south face of Mount Abundance (photos and details). Avoidance is the management strategy with slides of this size. The likelihood of triggering an avalanche is decreasing, but the potential size and destructive force are not. Carefully evaluate your route choices and the snowpack for signs of instability. The danger is MODERATE.

In the Northern Gallatin and Northern Madison Ranges and the mountains around West Yellowstone human-triggered avalanches are possible ranging from loose snow sluffs that could tumble a skier or rider through steep terrain to slab avalanches breaking 1-2’ deep on buried weak layers. Saturday’s rider-triggered avalanche near Two Top outside of West Yellowstone would have been dangerous on a larger slope (photos and details). Avalanches breaking deep in the snowpack are unlikely. Assess the snowpack for instability and mitigate the consequences of a mistake by carrying rescue gear, exposing only one person at a time to steep slopes and watching your partners. The danger is MODERATE.

Human-triggered avalanches are possible in the Southern Madison and Southern Gallatin Ranges on slopes where drifts from the last week sit on weak layers in the snowpack buried 6-18” deep. Areas below cornices and slopes where the recent snow seems deeper than other areas are suspect. Digging down to test the upper two feet of the snowpack will tell you a lot about overall stability. On slopes without recent wind-loading, large avalanches are unlikely. Assess the snowpack for isolated instabilities and follow safe travel protocols. The avalanche danger is MODERATE on wind-loaded slopes and LOW on all others.

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 Education Opportunities

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

March 4, Companion Rescue Clinic with the Bozeman Splitfest. Information and registration HERE.

Every Saturday near Cooke City, 10 a.m.-3 p.m. FREE snowpack update and transceiver/rescue training. Stop by for 20 minutes or more at the Round Lake Warming Hut.

The Last Word

In this article, Beyond the beacon: Thoughts and gear for a safe backcountry experience, Dave Zinn recounts his recent backcountry accident and how being prepared made a difference.