21-22

<p>The mountains near Cooke City received 2 feet of snow (equal to 2.3” snow water equivalent) since last Monday. Avalanches breaking below this snow are possible to trigger and could be large enough to bury a person, especially where recent snow has been drifted into slabs 1-3 feet thick. Strong wind will continue to grow these slabs today. Be extra cautious of steep, wind-loaded slopes. On Friday, skiers reported stability tests breaking below the recent snow (<strong><a href="https://www.mtavalanche.com/images/21/woody-ridge-profile-10-dec-2021">… profile</a></strong>) which shows the potential to trigger slides. Avalanches breaking deeper than the recent snow are unlikely, but we have found weak layers deeper in the snowpack that are worth digging to look for and evaluate before riding steep slopes (<a href="https://www.youtube.com/watch?v=1Nt5LOMI1PQ"><strong>video</strong></a&…;, <a href="https://youtu.be/O29XGDZBL8c"><strong>video</strong></a&gt;). Today, human triggered avalanches are possible and the avalanche danger is MODERATE.</p>

<p>Yesterday my partner and I skied at Mt. Blackmore in Hyalite and experienced constant 30-40+ mph winds (<strong><a href="https://www.youtube.com/watch?v=lyl9dBUt0u4&amp;list=PLXu5151nmAvT1nrM2…;) which occurred throughout the advisory area. In the mountains near Bozeman, Big Sky and West Yellowstone the strong south-southwest winds created fresh drifts of snow that a person could trigger today. These drifts might exist on any aspect, near ridgelines, across the middle of slopes, and locations where we don’t usually expect snow to be drifted into slabs. Look for cracking around your skis or sled as a sign the drifted snow is unstable. If you see these signs, stay off steep, wind-loaded slopes, especially where the consequences of getting caught in a slide involve being pushed over cliffs, or into rocks, trees, or gullies. 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 do not have fresh drifts the snowpack is generally stable. There are weak layers that have formed, but they are not much of a concern until we receive more snow (<a href="https://www.youtube.com/watch?v=8yJ1-BzM8Eg&amp;list=PLXu5151nmAvT1nrM2… video</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>

<p>Avalanches breaking 1-3 ft deep beneath this week’s new snow are the primary concern today, particularly where strong winds have blown loose surface snow into new and deeper drifts. Strong southwest winds today will actively be forming new drifts. Skiers south of town yesterday got unstable test results on the new snow - old snow interface, showing that the potential for triggering slides exists. There are also weak layers lower in the snowpack that are worth looking for and evaluating before riding steep slopes (<a href="https://www.youtube.com/watch?v=1Nt5LOMI1PQ"><strong><u>video</u></stro…;, <a href="https://youtu.be/O29XGDZBL8c"><strong><u>video</u></strong></a&gt;).&nbsp;</p>

<p>Human triggered avalanches are possible and the avalanche danger is MODERATE today.</p>

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<p>Avalanches breaking in wind drifts are also the number one concern near Bozeman, Big Sky, and West Yellowstone. Yesterday, Alex found thin fresh wind drifts in the Bridger Range that were very easily triggered (<a href="https://www.youtube.com/watch?v=sHEVrAd_rvI"><strong><u>video</u></stro…;). While the drifts he found were thin and harmless, deeper drifts pose a very real hazard. Even in places without new snow, increasingly strong winds have formed fresh drifts. The strong winds mean these drifts may have formed in atypical locations, mid-slope or further below ridgelines than usual. Be on the look out for pillows of drifted snow. If there are any signs these drifts are reactive, steer clear of them on steep slopes. Even if they’re not giving you any warning signs, keep up a healthy skepticism (<a href="https://www.youtube.com/watch?v=065JmnekjVs&amp;list=PLXu5151nmAvT1nrM2… Hyalite gullies video</u></strong></a>).</p>

<p>On non-windloaded slopes, conditions are mostly stable. There are weak layers that we’ll be monitoring, but they are not currently a major concern (<a href="https://www.youtube.com/watch?v=8yJ1-BzM8Eg&amp;list=PLXu5151nmAvT1nrM2… video</u></strong></a>).</p>

<p>The avalanche danger today 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><u>websi…;, email (<a href="mailto:mtavalanche@gmail.com"><strong><u>mtavalanche@gmail.com</u></str…;), phone (406-587-6984), or Instagram (#gnfacobs).</p>