21-22

<p>The mountains around Cooke City received 7” of snow overnight equal to 0.6” of <a href="https://missoulaavalanche.org/2021/01/what-is-swe-snow-water-equivalent… water equivalent</u></a> (SWE). Continued heavy snowfall through the morning in conjunction with increasing winds today will create dangerous avalanche conditions in wind-loaded terrain where human-triggered avalanches are likely. Yesterday, my partner and I observed generally stable conditions, but, today, will be carefully assessing for signs of increased instability and testing weak layers in the mid and lower snowpack now that they are loaded by new snow (<a href="https://www.youtube.com/watch?v=4GrVPi-1FC8&amp;list=PLXu5151nmAvT1nrM2…;). Avoid steep wind-loaded slopes and carefully evaluate terrain and snowpack conditions before entering avalanche terrain.&nbsp;</p>

<p>The avalanche danger is CONSIDERABLE on wind-loaded slopes and MODERATE on all others.</p>

<p>The Bridger, Madison, and Southern Gallatin Ranges received 4-6” of snow equal to 0.4-0.6” of SWE in the last 24-hours. Southwest winds are transporting the new snow into drifts on wind-loaded slopes where instabilities will be the most evident. Recent avalanches in the Bridger Range on Thursday (<a href="https://www.mtavalanche.com/node/25164"><strong><u>photos and details</u></strong></a>) and the Taylor Fork (<a href="https://www.youtube.com/watch?v=PPHZEgnv4lM"><strong><u>video</u></stro…;) and Bacon Rind (<a href="https://mtavalanche.com/images/21/avalanche-bacon-rind-photo-15-dec-202…;) on Wednesday are indicators of the types of avalanches we are concerned about. Evaluate snowpack stability, paying special attention to wind-loaded slopes, and assess terrain for features such as cliffs, rocks, trees, and gullies that amplify the consequences of even a small avalanche prior to entering steep terrain.&nbsp;</p>

<p>Areas south of Big Sky received nearly 3’ of snow within the last week, avalanches failing 1-3’ deep under last week’s storm snow less likely but remain a possibility.&nbsp;</p>

<p>Human-triggered avalanches are possible and the danger is rated MODERATE.</p>

<p>The northern Gallatin Range received 1” of snow in the last 24 hours while the Lionhead area remained dry. Wind from the southwest is creating fresh drifts of snow where avalanches are most likely to fail today. Similar to recent avalanches in the Southern Madison Range, these slides could be relatively small to 1-3’ deep breaking under last week’s snow (<a href="https://www.youtube.com/watch?v=PPHZEgnv4lM"><strong><u>video</u></stro…;, <a href="https://mtavalanche.com/images/21/avalanche-bacon-rind-photo-15-dec-202…;). Yesterday, groups of skiers testing the snowpack in Hyalite found both stable and unstable conditions illustrating the importance of assessing the specific terrain you are considering. Today, avoid freshly wind-loaded slopes where the danger is the greatest and assess the snowpack stability before traveling in steep terrain. Human-triggered avalanches are possible and the danger is rated MODERATE.&nbsp;</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><u>websi…;, email (<a href="mailto:mtavalanche@gmail.com"><strong><u>mtavalanche@gmail.com</u></str…;), phone (406-587-6984), or Instagram (#gnfacobs).</p>

<p>Strong west-southwest wind will drift snow from the past week into fresh slabs that skiers or riders could trigger. A person could also trigger avalanches of older drifts that formed over the past week. These wind slabs could range from 6 inches to 4 feet in depth. Avalanches are possible similar to those recently triggered by skiers and riders, such as a skier triggered slide at Bridger on Thursday (<a href="https://www.mtavalanche.com/node/25164"><strong>photos and details</strong></a>), a snowmobile triggered slide in the Taylor Fork (<a href="https://www.youtube.com/watch?v=PPHZEgnv4lM"><strong>video</strong></a&…;), and a skier triggered avalanche at Bacon Rind on Wednesday (<a href="https://mtavalanche.com/images/21/avalanche-bacon-rind-photo-15-dec-202…;). Be extra cautious of wind-loaded slopes, especially in terrain where the consequences being caught in a slide are high, like where you would be pushed into trees, over cliffs, dragged through rocks, or buried deeply in a confined gully.</p>

<p>Additionally, if you plan to ski or ride steep slopes dig to look for and evaluate the stability of buried weak layers. We have seen minimal evidence to indicate widespread buried weak layers exist, but with each load of new snow or fresh wind slabs we could see avalanches break deeper in the snowpack. Stay on the lookout for unstable buried weak layers, especially on slopes that held snow from October and early November.</p>

<p>Today, avalanches are possible to trigger and the avalanche danger is MODERATE.</p>

<p>Near Cooke City, strong west-southwest wind will drift snow into fresh wind slabs that skiers or riders could trigger. Older wind slabs 1-3 feet thick that formed over the past week are also possible to trigger, similar to a slab that snowmobilers triggered on Wednesday near Goose lake (<a href="https://www.mtavalanche.com/node/25168"><strong>details</strong></a&gt;). On non-wind loaded slopes avalanches are unlikely. If you plan to ski or ride steep slopes dig to look for potential unstable buried weak layers, and carefully assess the stability of wind-drifted snow.</p>

<p>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>