23-24
Cracking and collapsing north of Cooke City
Yesterday (1/9) touring north of Cooke City I felt some large collapses and cracking on a heavily wind loaded, mid elevation slope. There was about 4-6 inches of new snow that fell throughout the day.
GNFAC Avalanche Forecast for Wed Jan 10, 2024
<p><span><span><span><span><span><span>The avalanche danger is HIGH in the southern mountains and an Avalanche Warning has been issued. Since Friday these mountains have gotten a little bit of snow each day totaling 12-18” (1” </span></span></span></span></span></span><a href="https://avalanche.org/avalanche-encyclopedia/snowpack/snowpack-observat…;). Wind in the last 36 hours has blown at all elevations further loading slopes. The snowpack is historically weak which is outlined in this </span></span></span></span></span></span><a href="https://youtu.be/K_t6Fi6wUC4"><span><span><span><strong><span><u><span>… compilation</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>. Yesterday I was in Lionhead and found very poor stability in our snowpit at 8,000’, widespread cracking and collapsing at 8,300’ feet, and we intentionally triggered a 1,000’ wide avalanche at 8,600’ (</span></span></span></span></span></span><a href="https://youtu.be/QNkJeGFSPYs"><span><span><span><strong><span><u><span>…;, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29836"><span><span><span><strong><span… and observation</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Our advice is simple: Do not go into or underneath avalanche terrain. Avalanches can be triggered from far away and they will be large and deadly. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>The mountains around Bozeman and Big Sky have a couple feet of weak, faceted snow that is capped by 4-6” that fell since Saturday night (.4-.6” </span></span></span></span></span></span><a href="https://avalanche.org/avalanche-encyclopedia/snowpack/snowpack-observat…;). Strong and gusty wind has swirled and loaded slopes at all elevations. The interface between recent snow and older snow is unstable. Typically, 6” of snow over 4 days is nothing to worry about, but these are not typical times. My uncertainty regarding stability is high and I am worried. Given the wind and new snow, triggering avalanches is likely, especially slopes with a wind drift. Notch your travel plans back and be extra cautious and vigilant. Cracking, collapsing and avalanche activity are obvious signs to stay away from steep slopes. Today is not a day to push your luck. If you need evidence of the instability, check out our </span></span></span></span></span></span><a href="https://www.youtube.com/playlist?list=PLXu5151nmAvSH326zVaU9KXJAPtvkIt-… videos</span></span></u></span></strong></span></span></span><span><span><span><span><span><u><span><span> </span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>and </span></span></span></span></span></span><a href="https://www.mtavalanche.com/snow-observations-list"><span><span><span><… page</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>The avalanche danger is rated CONSIDERABLE. </span></span></span></span></span></span></p>
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.
Weather and Avalanche Log for Wed Jan 10, 2024
AVALANCHE WARNING: Cooke City, Lionhead, Island Park
GNFAC Avalanche Forecast for Wed Jan 10, 2024
Remotely Triggered Avalanche in Lionhead
While approaching Lionhead Ridge skiers intentionally triggered an avalanche on the steep E, NE facing terrain below the ridge. This likely happened on a buried layer of surface hoar. Lower down widespread cracking was observed that extended well in font of the skiers and on a less steep slope cracking in all directions 50' wide. Along the ridgetop cracking continued and sections of cornice fell and avalanched below.
Skier Triggered and Natural Avalanches in Hyalite
A skier at Mt. Blackmore saw multiple natural avalanches and one skier triggered avalanche. These likely happened earlier in the day or the day prior, 01/07.
Seen on a ski tour on 1/08. From Obs: Notice a few natural avalanches and one skier triggered avalanche near of the top of Blackmore. Looked as though it was a ski cut that popped the slab. Photo: S. Lowe
Forecast link: GNFAC Avalanche Forecast for Thu Jan 11, 2024
Cornices easily broke while walking near them and avalanched onto the slope below. The slope below had already avalanched from a remote trigger below the ridgeline. Photo: GNFAC
Forecast link: GNFAC Avalanche Forecast for Wed Jan 10, 2024