Good Morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Friday, December 8th at 6:45 a.m. Today’s advisory is sponsored Beartooth Powder Guides and Montana Ale Works sponsor today’s advisory. This advisory does not apply to operating ski areas.
Overnight the mountains around Cooke City picked up a trace to 1” of new snow, while rest of the advisory area remained dry. This morning temps range from the teens to upper 20’s F under mostly clear skies. Winds are blowing 15-30 mph out of the W-NW with the exception of the Bridger Range where they’re blowing out of W-SW. Today, temps will warm into the upper 20’s to low 30’s F under sunny skies. Winds will remain light to moderate out of the W-NW. The dominating ridge of high pressure parked over the area will produce a benign weather pattern through the foreseeable future.
Strong winds out of the west-southwest continue to hammer the Bridger Range. These relentless winds have affected the snowpack on all aspects and elevations. Some slopes are scoured to the Thanksgiving ice crust, while others are heavily loaded. Yesterday, the Bridger Bowl Ski Patrol did control work in anticipation of today’s opening and triggered wind slabs across the mountain. These slabs are becoming more stubborn but could still fail under the weight of a skier or rider.
Wind loaded slopes are also the main avalanche concern in the mountains around Cooke City. This problem is more confined to upper elevation ridgelines. Yesterday and overnight, winds around Cooke City blew 30-50 mph out of the W-NW. These strong winds likely formed fresh wind slabs in upper elevation, leeward terrain. Exercise caution when traveling in wind loaded areas, especially in steeper-high consequence terrain.
Outside of the wind loaded slopes, the snowpack is mostly stable in the Bridger Range and mountains around Cooke City (video).
Today, human triggered avalanches are possible on wind loaded slopes which have a MODERATE avalanche danger. Non-wind loaded slopes have a LOW avalanche danger.
Clear and calm conditions yesterday gave wind slabs that formed earlier in the week a chance to stabilize. Yesterday, we travelled into wind loaded gullies around Hyalite to assess stability for the Bozeman Ice Festival. We found mostly stable conditions, with recently formed wind slabs bonding well to the old snow surface (video). This is consistent with observations from around the area (video).
Yesterday, the Yellowstone Club Ski Patrol did extensive control work for the first time this season with minimal results. At this point, the snowpack in the Yellowstone Club is representative to a backcountry snowpack. This a solid indicator stability is generally good. This is consistent with what Alax and his partner found in the Taylor Fork yesterday.
Without a significant weather change, the snowpack will remain generally stable. While natural and human triggered avalanches are unlikely, they are not impossible. Use standard backcountry protocol and always be thinking about the consequence of a slide.
Today, generally safe avalanche conditions exist and the avalanche danger is rated LOW.
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
Dec. 13, Avalanche Awareness, 6:30-8 p.m. at Gallatin Valley Snowmobile Association, 4-Corners
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
Dec. 14 and 15, Snowmobiler Introduction to Avalanches with Field Course, Info and Register Here
COOKE CITY
8 and 9 December, Current Conditions and Avalanche Rescue, 6:30-7:30 p.m. Friday @ the Super 8, and anytime between 10-2 on Saturday @ Lulu Pass road.
Check out this 2-minute video on the snowpack. Great graphics illustrate the process of sintering and faceting. Thanks to SINTR Visual Communications!