Snowpack and Avalanche Discussion
<p>Very dangerous avalanche conditions exist in the mountains around Cooke City, West Yellowstone, and Island Park. Human-triggered avalanches breaking 1-2 feet deep are very likely, especially on slopes at upper elevations, near ridgelines, or commonly affected by wind.</p>
<p>Instability was obvious yesterday at Lionhead when the first steep slope Alex and I approached had already avalanched naturally, and we triggered a large collapse and shooting cracks (<a href="https://www.youtube.com/watch?v=mSked07bAY8&lc=UgwOJBQp1Ujv-9h17St4…;). Last week in Cooke City, Ian and his partner remotely triggered an avalanche from hundreds of feet away (<strong><a href="https://www.youtube.com/watch?v=74rb5HCvbsE">video</a></strong>), and Doug and his partner discussed similar conditions in Island Park (<a href="https://www.youtube.com/watch?v=LzkWoa4viY0"><strong><span>video</span>…;). Avalanches, collapses, and cracks shooting long distances are the staples of all recent observations from <a href="https://www.mtavalanche.com/snow-observations-list?field_regions_simila… City</span></strong></a>, <a href="https://www.mtavalanche.com/snow-observations-list?field_regions_simila… Park</span></strong></a>, <a href="https://www.mtavalanche.com/snow-observations-list?field_regions_simila… Area</span></strong></a><strong><u><span>,</span></u></strong> and the <a href="https://www.mtavalanche.com/snow-observations-list?field_regions_simila… Madison</span></strong></a> and <a href="https://www.mtavalanche.com/snow-observations-list?field_regions_simila… Gallatin Ranges</span></strong></a>.</p>
<p>Today, ride or ski in low-angle meadows and low-angle trees while avoiding travel on slopes steeper than 30 degrees or the flatter terrain immediately below.</p>
<p>The avalanche danger is HIGH on wind-loaded slopes and CONSIDERABLE on all others.</p>
<p>Dangerous avalanche conditions exist in the mountains around Bozeman and Big Sky. We have discussed the exceptionally weak snowpack in the northern portions of the advisory area all season. This weekend, we turned a dangerous corner in the evolution of the season’s snowpack, and instability is showing its face.</p>
<p>In the last two days, we received reports of nearly a dozen natural and human-triggered avalanches and more indicating unstable snow (<a href="https://www.mtavalanche.com/avalanche-activity"><strong><span>avalanche activity log</span></strong></a>).</p>
<p>Standout events include:</p>
<ul>
<li>A close call on Saddle Peak yesterday, when a skier descending the Skyline Ridge triggered a slab that broke 2-3 feet deep, ultimately propagating 500 feet wide and running over 1000 vertical feet (<a href="https://www.mtavalanche.com/node/30161"><strong><span>details and photos</span></strong></a>).</li>
<li>A skier reacting quickly to dodge an avalanche that he triggered remotely from low down in the bowl on Flanders Mountain (<a href="https://www.mtavalanche.com/node/30123"><strong><span>details and photos</span></strong></a>).</li>
<li>A pair of skiers below Hyalite Peak triggered an avalanche from 400 feet away. Thankfully, both were out of harm’s way (<a href="https://www.mtavalanche.com/node/30129"><strong><span>details and photos</span></strong></a>).</li>
<li>Multiple large, natural avalanches on Cedar Mountain spotted by the Big Sky Ski Patrol (<a href="https://www.mtavalanche.com/node/30110"><strong><span>details</span></s…;).</li>
</ul>
<p>Levels of uncertainty are higher than normal. Weigh heavily recent evidence of instability whether they be from persistent weak layers or wet snow. Minimize exposure to avalanche terrain, thoroughly assess the snowpack, and employ conservative decision-making.<br />
<br />
The avalanche danger is rated CONSIDERABLE.</p>
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.
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.