Snowpack and Avalanche Discussion
<p><span><span><span><span><span><span>Heavy new snow and strong wind are creating very dangerous avalanche conditions on wind-loaded slopes. Human-triggered and natural avalanches are likely where wind is drifting the new snow into thicker slabs and overloading buried weak layers. Avalanches breaking in the new and wind-drifted snow will be large enough to be potentially deadly, and very large avalanches could break several feet deep on weak layers that were buried months ago. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Since late February we have seen huge human-triggered and natural avalanches that broke deep in the snowpack. The most recent were just over a week ago near Cooke City, triggered by snowmobilers (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/28785"><span><span><span><strong><span… Pass</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/28695"><span><span><span><strong><span… Mtn.</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Similar slides are likely today. On non-wind loaded slopes the likelihood is lower, but dangerous avalanches can be triggered on any slopes steeper than 30 degrees. Avoid riding across and underneath steep slopes. Avalanche danger is HIGH on wind-loaded slopes and CONSIDERABLE on non-wind loaded slopes.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>The mountains near Bozeman and Big Sky received less snow, but plenty of wind over the last 24 hours. On wind-loaded slopes, human-triggered avalanches are likely. Fresh drifts of snow will be easy to trigger, and avalanches could break on weak layers buried below last week’s heavy snowfall or deeper on weak layers that were buried in January. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>On Thursday in the Lone Lake Cirque near Big Sky resort, a snowboarder took a ride over huge cliffs in a slide that broke at least 2-4 feet deep (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/lone-lake-cirque-slide"><span><sp…;). On Friday, a fresh natural wind slab was seen on Cedar Mountain (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/natural-cedar-mountain"><span><sp…;), and in Portal Creek riders triggered a 2-3 ft deep avalanche from 100 ft away (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/28887"><span><span><span><strong><span… and photos</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). The slide in Portal Creek likely broke below last week’s snow on weak faceted snow that has remained unstable. Yesterday in the northern Bridger Range, skiers saw a recent very large natural avalanche that broke several feet deep and 500 feet wide (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/28900"><span><span><span><strong><span… and photos</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>Plan to avoid steep wind-loaded slopes. Before traveling across any steep slopes carefully assess the snowpack for recent wind-loading and buried weak layers, and choose slopes with minimal hazards like trees or cliffs in the runout zone. The avalanche danger is CONSIDERABLE on wind-loaded slopes and MODERATE on non-wind loaded slopes.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Please share avalanche, snowpack or weather observations via our website, email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).</span></span></span></span></span></span></p>
<p>Heavy new snow and strong wind are creating very dangerous avalanche conditions on wind-loaded slopes. Human-triggered and natural avalanches are likely where wind is drifting the new snow into thicker slabs and overloading buried weak layers. Avalanches breaking in the new and wind-drifted snow will be large enough to be potentially deadly, and very large avalanches could break several feet deep on weak layers that were buried months ago. Avoid riding across and underneath slopes steeper than 30 degrees.</p>
