17-18
The north face of Cedar Mountain avalanched full depth sometime on Jan 1 or morning of January 2. This slope is called "Dirty Bowl" and it appears an impact crater (rockfall, cornice fall) may have triggered the slide. Photo: C. Connor
Truman Gulch Avalanche
On Friday, December 29th 2017, a group of 3 skiers exited the Bridger Bowl Ski Area west boundary to access the backcountry terrain in Truman Gulch. The group skied one run and climbed with skis and skins back to the ridge dividing backcountry and ski area. They skied a second run adjacent to their ascent route which they ascended again on the same track. Then the group split up. Skier 1 skied a gully north of their previous run.
Two skiers were caught and partially buried in a avalanche below the cliffs of saddle peak on 1/2/2018.
The north face of Cedar Mountain avalanched full depth sometime on Jan 1 or morning of January 2. This slope is called "Dirty Bowl" and it appears an impact crater (rockfall, cornice fall) may have triggered the slide. Photo: Big Sky Ski Patrol
Forecast link: GNFAC Avalanche Forecast for Wed Jan 3, 2018
This big natural avalanche on the East aspect of Emigrant Pk is outside our forecast area, but reminds us that snow is unstable in our surrounding areas. It likely ran Saturday or Sunday from a wind loaded NE aspect below the summit into low angle terrain, at least 2500' vertical total. It completely crossed a previous group's skin track and ski tracks. Photo: J. Curry
GNFAC Avalanche Advisory for Tue Jan 2, 2018
Snowpack and Avalanche Discussion
<p>The storm ended on Saturday and dropped over 4’ of snow outside Cooke City, 2-3’ in other ranges and a foot near West Yellowstone. Yesterday was the first day in almost a week without recent avalanches or signs of instability. Many natural avalanches and human triggered slides occurred during the storm. There were a couple of close calls when a skier was caught and injured in Truman Gulch on the west side of the Bridger Range on Friday (<a href="https://youtu.be/7ETCg89ANx0"><strong>video</strong></a>, <a href="https://www.mtavalanche.com/images/17/truman-gulch-crown-skier-triggere…;) and a skier was partially buried outside Cooke City after remotely triggering an avalanche from below on Thursday. For an inventory of the avalanche cycle, check out our <a href="https://www.mtavalanche.com/photos"><strong>Photos page</strong></a> or daily synopsis of avalanche activity in our <a href="https://www.mtavalanche.com/weather/wx-avalanche-log"><strong>Weather and Avalanche Log</strong></a>.</p>
<p>Avalanches were especially numerous on slopes with a shallow snowpack, typically at lower elevations, since they harbor weak snow near the ground and also around an ice crust that formed over Thanksgiving. Some avalanches in the alpine were large and deep and broke on weak, faceted snow that formed at the surface mid-December.</p>
<p>On Sunday skiers reported collapsing and cracking near Lionhead (Hebgen Lake area) and Cooke City. As the days pass without new snow or significant wind-loading, the likelihood of triggering avalanches decreases, but my hackles are raised. Seeing avalanche crowns is exciting, but should serve as a reminder to be extra careful, even with stability getting better. Yesterday, folks in the northern Bridger Range did not ski their intended line after seeing avalanches from the storm and facets in the snowpack (<strong><a href="https://www.mtavalanche.com/images/18/avalanche-crowns-near-brackett-cr…;). I recommend 2 things to stay safe out there today:</p>
<ol>
<li>Stay off of wind-loaded slopes.</li>
<li>Do a stability test before committing to avalanche terrain. If the test breaks easy and clean, go elsewhere. <em>If you have no idea what I’m talking about, check out our <strong><a href="https://www.youtube.com/playlist?list=PLXu5151nmAvSpq8PsgPGnkKM-DKvTEKT… video playlist</a>.</strong></em></li>
</ol>
<p>To dive deeper into our current concern regarding snowpack structure, check out our recent videos from the <strong><a href="https://youtu.be/uyHF7iKRjtM">Yellow Mountain</a></strong>, <strong><a href="https://youtu.be/iEGue4T9rzo">Bacon Rind</a></strong> and <strong><a href="https://youtu.be/85UQeqSWXqk">Lionhead</a></strong> as well as our <strong><a href="https://www.mtavalanche.com/snowpits">snowpits</a></strong>. For today, the avalanche danger is rated <strong>MODERATE</strong> on all slopes since human triggered avalanches are still possible.</p>
<p>If you get out and have any avalanche or snowpack observations to share, drop a line via our <a href="https://www.mtavalanche.com/node/add/snow_observation">website</a>, email (<a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a>), phone (406-587-6984), or Instagram (#gnfacobs).</p>
Upcoming Avalanche Education and Events
BOZEMAN
TOMORROW, Jan. 3, Avalanche Awareness, 6-7 p.m. at REI Bozeman
Jan. 12 and 13, Companion Rescue Clinic, Info and Register
Weather and Avalanche Log for Tue Jan 2, 2018
Avalanche Fatality; Bridger had strong downhill winds.
These shallow avalanche crowns were south of the Throne near Brackett Creek. photo: E. Stifler
Forecast link: GNFAC Avalanche Advisory for Tue Jan 2, 2018
Avalanche crowns are numerous around Cooke City. This one was spotted a few days ago at the Dump. Photo: S. Magro
Forecast link: GNFAC Avalanche Advisory for Tue Jan 2, 2018