GNFAC Avalanche Forecast for Fri Jan 1, 2021

Not the Current Forecast

Good Morning. This is Ian Hoyer with the Gallatin National Forest Avalanche Forecast on New Year’s Day, January 1st at 7:15 a.m. This forecast is sponsored by Blitz Motorsports and Yamaha and Gallatin Valley Snowmobile Association. This forecast does not apply to operating ski areas.

Mountain Weather

As snowfall finished up yesterday morning, the Lionhead area picked up an additional 3” of new snow and a trace to 1” fell elsewhere. Winds are 10-20 mph out of the west across most of the advisory area, with 25 mph steady winds and 40 mph gusts in the Bridger Range this morning. Skies are partly cloudy with temperatures in the mid-teens and 20s F. Winds will continue to blow out of the west at 10-20 mph, with stronger gusts in the Bridgers. Temperatures will rise into the mid-20s and low-30s F. Light snowfall tonight will bring a trace to an inch of new snow by tomorrow morning.

Snowpack and Avalanche Discussion

While the Bridger Range and Lionhead area are a two hour drive apart, you’ll find similar conditions in the two areas today. These areas saw the most snowfall out of this last storm (5-6”) and in the case of the Bridgers, also the strongest winds (with gusts of 40 mph). This combination, on top of a weak lower snowpack, has created unstable conditions and avalanches will be easily triggered today on wind-loaded slopes. With increased winds overnight in the Bridger Range, expect to find newly formed and thicker wind drifts today. 

Unfortunately, the snowpack is bringing 2020’s problems into the new year. The weak snow at the ground has shown it can’t handle a load. Each time we’ve gotten even a small snowfall we’ve seen signs of instability, either avalanches or dramatic “whumpfs” and collapsing of the snowpack (video). Expect the same today. If you get onto a steep windloaded slope, you are likely to trigger a slide. Avoid steep windloaded slopes and carefully assess all other steep slopes.

The avalanche danger is CONSIDERABLE on windloaded slopes today and MODERATE on all other slopes. 


The Madison and Gallatin Ranges have the same weak snowpack, just with a slightly smaller load of new snow. Triggering an avalanche on weak snow near the ground is a very real possibility. Stay on alert for bullseye signs of instability - recent avalanches, collapses, or shooting cracks. If you don’t see these clear signs, dig a snowpit and keep searching for instability (video). We’ve seen avalanches even with small loading events this year and just can’t trust this snowpack (video). 

Human triggered avalanches are possible and the avalanche danger is MODERATE.

You are unlikely to trigger an avalanche today near Cooke City. However, if you get unlucky and find just the wrong spot you could still trigger a slide. On Wednesday morning, a snowmobiler triggered a slide on Crown Butte that ran 400 vertical feet and piled up debris that was easily deep enough to bury someone (video). This is a good reminder to always be prepared and carry rescue gear so you’re ready to respond if something goes wrong. The avalanche danger is LOW today.

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:

Every Saturday in Cooke City, FREE snowpack update and rescue practice at the Round Lake Warming Hut between 10 a.m. and 3 p.m. Poster with More Info.


Tuesday, January 5, 6-7 p.m. The Friends of the Avalanche Center will offer a FREE 1-hr Avalanche Awareness Talk in partnership with The Basecamp and Alpine Orthopedics and Sports Medicine. The talk will be a live, ONLINE event. Join us HERE:

Monday, January 11, 6-7 p.m. The Friends of the Avalanche Center will offer a FREE 1-hr Avalanche Awareness Talk in partnership with Uphill Pursuits. The talk will be given via a live ZOOM session. Please click the link below to join the webinar:


Tuesday, January 19, 6-7 p.m. The Friends of the Avalanche Center will offer a FREE 1-hr Avalanche Awareness Talk in partnership with the University of Montana Western School of Outreach. The talk will be a live, ONLINE event. Join us HERE:


January 20 & 21 (plus field sessions the following weekends), Avalanche Fundamentals with Field Course. There are separate field sessions tailored for both skiers and splitboarders (Bridger Bowl) and snowmobilers (Buck Ridge). Register here.


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