This is Dave Zinn with the avalanche forecast for Tuesday, January 7th, at 7:00 a.m. This forecast is sponsored by Gallatin County Sheriff Search and Rescue and Highline Partners. This forecast does not apply to operating ski areas.
This morning, temperatures are in the single digits to teens F, with light winds except in the Bridger and Lionhead areas, where winds are 15 mph, gusting to 35 mph. The Northern Madison and Northern Gallatin Ranges picked up another 3-4” of snow in the last 24 hours, with 0-1” elsewhere.
Today, temperatures will reach the teens and 20s F with light winds from the north and west. Localized winds may increase in the Bridger Range. Clouds will gradually clear away after a trace of snow falls this morning. Snow returns tomorrow afternoon.
Snow has fallen across the majority of the advisory area all but one day in the last two weeks, adding up to feet of snow and dangerous avalanche conditions (weather log for specifics). Don’t let clearing skies inspire undue confidence in the snowpack. Human-triggered avalanches are likely.
The threat of persistent slab avalanches failing on weak layers of sugary facets and feathery surface hoar buried 2-4 feet deep (deeper on wind-loaded slopes) inspires conservative decision-making and cautious route-finding that generally avoids slopes steeper than 30 degrees. Since Friday, the largest two slides we know about failed 600 feet wide in the Lionhead area (photos and details) and 3-4 feet deep on the shoulder of Sheep Mountain in Cooke City (photos and details). Go to the avalanche log on the website to read about nearly two dozen avalanches recorded since Friday. With increasing visibility, we expect to add to the list.
Adhere to the basics of avalanche safety: beacon, shovel, probe, partner and only expose one at a time to steep terrain. If you stray into the peripheries of avalanche terrain, carefully consider the consequences of a potential slide.
The danger is CONSIDERABLE.
The Bridger Range has racked up 44” of snow in the last week, with daily accumulation. Wind slab avalanches are the primary problem today.
Yesterday, a skier triggered an avalanche near the ridgeline of South Saddle Peak in the terrain loaded with drifting snow. The slide ran 1500 vertical feet, broke 6” diameter trees and piled debris 20 feet deep (details and photos). This weekend, a separate slide in Argentina Bowl broke 500 feet wide (photo and details), and skiers triggered a 200-foot-wide wind slab avalanche at the top of the Ramp. (photo and details). Today’s wind patterns in the Bridger Range may deposit unstable slabs in mid and lower-elevation terrain as well as near ridgelines. Avoid wind-loaded slopes by noticing visual clues of drifting, a stiffening of the snow surface and signs of instability, such as recent avalanche activity and shooting cracks.
While we haven’t recorded persistent slab avalanches in the Bridger Range, don’t ignore buried weak layers and their threat—continuous loading for more than a week warrants careful snowpack assessment evaluating for instability and cautious route finding.
Human-triggered avalanches are likely, and the avalanche danger is CONSIDERABLE.
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar
TOMORROW: Wednesday, January 8, 2025, 7-9:30 p.m., Avy Savvy Night at the Colonial Theater, Idaho Falls. More information HERE.
We offer Avalanche Fundamentals with Field Session courses targeted towards non-motorized travelers VERY SOON in January and one geared towards motorized users. Sign up early before they fill up.
Every weekend in Cooke City: Friday at The Antlers at 7 p.m., Free Avalanche Awareness and Current Conditions talk, and Saturday from 10 a.m.-2 p.m. at Round Lake Warming Hut, Free Rescue Practice.
THANK YOU - Fall fundraiser
On behalf of the Friends of the Avalanche Center, we would like to extend our heartfelt thanks for your generous support of the Powder Blast fundraiser. This is our largest fundraiser of the year. We are thrilled to share that, thanks to your contributions and the incredible generosity of an anonymous donor, we have successfully met our fall fundraising goal.
Tragically, a skier was killed, and a second sustained injuries in an avalanche in western Wyoming on Sunday (preliminary information). This is the fifth avalanche fatality this season. Our hearts go out to the skiers’ friends and family, backcountry partners, and the rescue teams.