Good Morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Tuesday, December 26th at 7:15 a.m. Today’s advisory is sponsored by Montana Ale Works and Montana State Parks. This advisory does not apply to operating ski areas.
In the last 24 hours the northern mountains picked up 7-9” of new snow, Cooke City has 6” and 3” fell around West Yellowstone and the southern Madison Range. Winds are averaging 20 mph from the W-NW with gusts of 50 mph around Big Sky. Mountain temperatures are in the low single digits and will rise into the mid-teens today. Other than a few flurries this morning, today will become sunny and then cloud up tonight with decreasing, 10-20 mph west winds.
Yesterday’s 7-9” of snow in the northern ranges and 3-6” of snow in the south will be blown into drifts from last night and this morning’s windy conditions. These drifts can be triggered today. Yesterday, skiers to the west of Cooke City triggered an avalanche (no one was caught) that broke under new, windblown snow (photo1, photo2) and another skier south of Cooke City found similar instability (photo). Ridgetop winds have been westerly, but wind-loading may occur on many aspects since blowing snow does not always behave in an orderly way.
On some slopes it is possible to trigger an avalanche on a weak layer of facets buried 2-3 feet deep. I found this on Buck Ridge on Sunday (video) and saw one avalanche on a wind-loaded slope to the south (photo). Overall instabilities are not widespread and will not last long, which Eric noted in Taylor Fork (video) and Alex found in Cooke City (video). These facets are notably weaker in Lionhead, Bacon Rind (photo),the west side of the Bridger Range, and low elevation slopes; generally any area with a shallow snowpack.
Three steps to stay safe:
- Get caught up on all our recent photos and videos because seeing is believing.
- Stay clear of wind-loaded slopes since avalanches are likely to be triggered. Cracking or collapsing are signs of dangerous conditions.
- Dig 2-3’ deep to an ice layer that formed over Thanksgiving (you can’t miss it) and do a stability test. A clean break indicates instability.
For today, the avalanche danger is rated CONSIDERABLE on all wind-loaded slopes and MODERATE on all others.
If you get out and have any avalanche or snowpack observations to share, drop a line via our website, email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).
Upcoming Avalanche Education and Events
BOZEMAN
Jan. 3, Avalanche Awareness, 6-7 p.m. at REI Bozeman
Jan. 12 and 13, Companion Rescue Clinic, Info and Register
Jan. 17, 18 and 20 or 21, Introduction to Avalanches w/ Field Day, Info and Register Here
Jan. 24, 25 and 27, Advanced Avalanche Workshop w. Field Day, Info and Register Here
Feb. 9 and 10, Companion Rescue Clinic, Info and Register
WEST YELLOWSTONE
Jan. 6, Avalanche Awareness, 7-8 p.m. at West Yellowstone Holiday Inn Conference Center
BIG TIMBER
Jan. 11, Avalanche Awareness, 6-7 p.m. at Sweet Grass County High School
BUTTE
Jan. 13, Rescue Clinic, 10 a.m. at Homestake Lodge
Dillon
Jan. 16, Avalanche Awareness, 6:30-8 p.m. at U.M. Western Library
COOKE CITY
Every Friday and Saturday, Current Conditions Update and Avalanche Rescue, Friday 6:30-7:30 p.m. at Super 8 this week, and Antler's Lodge in January. Saturday anytime between 10-2 @ Lulu Pass road.