GNFAC Avalanche Forecast for Fri Feb 18, 2022

Not the Current Forecast

Good morning. This is Ian Hoyer with the Gallatin National Forest Avalanche Forecast on Friday, February 18th, at 7:00 a.m. This information is sponsored by Blitz Motorsports and Yamaha and onX. This forecast does not apply to operating ski areas.

Mountain Weather

In the last 24 hours, 3” of new snow fell in the Taylor Fork and near Cooke City, 1” in Hyalite and Lionhead, with no new snow in the Bridger Range or around Big Sky. Winds are 15-25 mph out of the southwest to northwest, with strong gusts (up to 60 mph in the Bridgers). Gusty southwest to west winds will continue today. Temperatures are in the teens and 20s F this morning and will rise into the high 20s and 30s F this afternoon. Snow flurries will bring less than an inch of new snow to most of the advisory area while Cooke City may see 2-3” accumulate by tomorrow morning.

Snowpack and Avalanche Discussion

The Bridger Range and mountains near Big Sky saw the most snowfall from this week’s storm (up to  1-1.5 ft of fresh snow). While some slopes had slightly less new snow, on others the new snow has been drifted into even deeper drifts. Yesterday, Alex and Doug were in the Bridgers and I was on Buck Ridge. In both places we only saw small avalanches breaking in the new snow, but identified the potential for larger slides (photo, Bridgers video, Buck Ridge video). Large avalanches are possible on any slope with more than around 8” of new or drifted snow. Avoid steep slopes where deeper cohesive drifts are likely, especially below corniced ridgelines. Avalanches could also break wider and less predictably on weak layers buried a few inches below the old snow surface. Triggering large avalanches is very much possible today and the avalanche danger is MODERATE.

 

Near Cooke City, there was less new snow, but it fell onto weak layers buried a foot and a half to two feet deep that avalanched after last week’s snowfall (Wyoming Creek avalanche details, Silver Gate avalanche details). Skiers on Henderson Mountain yesterday saw large drifts actively forming, which will make these weak layers even more sensitive. Triggering avalanches on these weak layers remains possible and the danger is MODERATE near Cooke City.

5-8” of new snow over the last four days in Hyalite, the southern Madison Range, and the Lionhead area accompanied by strong westerly winds means it is possible to trigger large avalanches on wind-loaded slopes. Weak layers in the upper snowpack are widespread but on slopes without a thicker slab of cohesive, wind-drifted snow, avalanches are unlikely. Steer clear of wind-loaded slopes to avoid triggering a large slide. 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.

TOMORROW! February 19, Women’s only Companion Rescue Clinic sponsored in partnership with SheJumps! Register Here.

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.