21-22

<p>The mountains near West Yellowstone, southern Madison and southern Gallatin Range are in the direct path of the incoming storm. Snowfall is expected this morning and will continue into Wednesday. Avalanche danger will begin to increase today, especially on wind loaded slopes where continued strong winds will blow snow into thick drifts. Yesterday Dave and his partner rode into Lionhead Ridge and had a thick drift collapse and “whumph” beneath their skis (<strong><a href="https://www.youtube.com/watch?v=Vo9-92FngRA&amp;list=PLXu5151nmAvT1nrM2…;). Skiers in the Taylor Fork sent this <strong><a href="https://www.mtavalanche.com/images/21/thick-wind-slabs-taylor-fork-0">p…; of a thick wind drift that broke on a small slope. Drifts of snow that formed from recent southerly winds overloaded weak layers and made the snowpack unstable. These drifts will continue to grow and become more unstable with new snow and strong wind today, and it will become likely for riders and skiers to trigger these drifts and cause avalanches on steep slopes. Be prepared to avoid steep, wind-loaded slopes today as they become more unstable.</p>

<p>Today, new snow and strong wind will increase the avalanche danger to CONSIDERABLE on wind-loaded slopes and MODERATE on all other slopes.</p>

<p>In the mountains near Bozeman, Big Sky and Cooke City recent strong southerly winds created unstable drifts that can avalanche under the weight of a person (<a href="https://www.youtube.com/watch?v=lyl9dBUt0u4&amp;list=PLXu5151nmAvT1nrM2… of strong wind</strong></a>). Yesterday multiple groups of climbers in Hyalite reported large drifts that cracked and “whumphed” under their feet (<strong><a href="https://www.mtavalanche.com/images/21/propagating-cracks-along-top-and-…;, <strong><a href="https://www.mtavalanche.com/images/21/cracking-drifts-hyalite">photo</a…;). These drifts formed above weak, sugary snow which means they will remain possible to trigger for a couple days (<strong><a href="https://www.mtavalanche.com/images/21/thin-snowpack-hyalite">photo of weak snow in Hyalite</a></strong>). The strong southerly winds formed drifts on many aspects, near ridgelines, across the middle of slopes, and locations where we don’t usually expect snow to be drifted into slabs. If you see cracking snow around your feet, stay off steep, wind-loaded slopes, especially where the consequences of getting caught in a slide involve being pushed into rocks, trees, gullies, or cliffs. Even without clear signs of instability, remain skeptical of wind-loaded slopes today (<a href="https://www.youtube.com/watch?v=065JmnekjVs&amp;list=PLXu5151nmAvT1nrM2… Hyalite gullies video</strong></a>).</p>

<p>On slopes that are not wind-loaded the snowpack is generally stable. There are weak layers that are worth digging to look for and assess, but they are of little concern until we receive more snow (<a href="https://www.youtube.com/watch?v=8yJ1-BzM8Eg&amp;list=PLXu5151nmAvT1nrM2… video</strong></a>, <a href="https://www.youtube.com/watch?v=1Nt5LOMI1PQ"><strong>Cooke City video 1</strong></a>, <a href="https://youtu.be/O29XGDZBL8c"><strong>Cooke City video 2</strong></a>).</p>

<p>Today the avalanche danger is MODERATE on wind-loaded slopes and LOW on all other slopes.</p>

<p>If you get out, please send us your observations no matter how brief. You can submit them via our <a href="https://www.mtavalanche.com/node/add/snow_observation"><strong>website<…;, email (<a href="mailto:mtavalanche@gmail.com"><strong>mtavalanche@gmail.com</strong></a…;), phone (406-587-6984), or Instagram (#gnfacobs).</p>