GNFAC Avalanche Forecast for Wed Jan 27, 2021

Not the Current Forecast

Good Morning. This is Dave Zinn with the Gallatin National Forest Avalanche Forecast on Wednesday, January 27th at 7:30 a.m. Today's forecast is sponsored by Blitz Motorsports and Yamaha and Gallatin County Search and Rescue. This forecast does not apply to operating ski areas.

Mountain Weather

Mountain temperatures are in the single digits to low teens F with 15-25 mph winds from the southwest and there is 1" of new snow in the mountains around West Yellowstone.

Today, temperatures will be in the upper teens to mid-20s F. West Yellowstone will receive 5-7" of new snow and Cooke City will receive an inch. The rest of the advisory area will get the associated 15-25 mph winds from the south to southwest. Snow will move north Friday night into Saturday.

Snowpack and Avalanche Discussion

The mountain snowpack from Lionhead through the Bridger Range is shallow with two distinct weak layers. The first is a thick layer of weak, sugary snow near the ground. This layer is nearly universal and has caused many avalanches this season, most recently a snowmobile-triggered avalanche in the Taylor Fork (2020-21 avalanche activity list, Taylor Fork details). It will take weeks or months to fully trust this layer of depth hoar, but it is adjusting to the current load and avalanches are less likely. The second is a thin layer of feathery surface hoar buried 6-18" deep. This layer is not everywhere and we have seen variations in its reactivity. During recent field days, Alex and I found it very reactive at Bacon Rind and in some areas of the Taylor Fork (Bacon Rind video, Taylor Fork video). We will watch this layer to see if it begins causing more problems in the future.

Stability in these ranges is currently similar, but today's snowfall will heavily favor the mountains around West Yellowstone. Stability will decrease as the snow adds up. Watch for new avalanche activity and shooting cracks and listen for "whumphing" as clear signs to retreat from steep slopes. Get your shovel out and perform an extended column test if you don't observe these obvious signs of instability.

Today, travel in and around steep terrain requires a conservative mindset, careful route-finding and thorough snowpack assessment. Human-trigger avalanches are possible and the danger is rated MODERATE.

The challenge in Cooke City is that many slopes are stable while some have one or two buried weak layers. The first is a recently problematic layer of surface hoar buried 12-18" deep and the second is a more dormant layer of sugary facets buried 2-3' deep. Last weekend, snowmobilers triggered three avalanches near Sheep Mountain and skiers saw shooting cracks and hear loud whumphs. Learn more by watching Doug's new video and looking at the photos from Cooke City (Huckleberry photo, Miller Ridge photo, Sheep Mountain photo, shooting cracks photo). Both weak layers are adjusting to their current load and, while avalanches remain possible, they are becoming less likely.

Variability between slopes requires riders and skiers to be attentive to changes in conditions, to plan routes carefully and to regularly search for signs of instability as a reason to back out of steep terrain. The danger is rated MODERATE.

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.

February 5 and 6, Women's Companion Rescue Clinic with SheJumps. Registration HERE.

February 19 and 20, Companion Rescue Clinic. Registration HERE

February 26 and 27, Women's Companion Rescue Clinic with SheJumps. Registration HERE.

King and Queen Fund-raiser

February 6th and 7th, Saturday and Sunday, at Bridger Bowl. Due to the pandemic it is a GS race this year. Prizes will be awarded for the fastest race results AND separate prizes for folks who raise the most money over $500. No racing is necessary to compete for the fundraising prizes. Info is HERE.