20-21

<p>Weak, sugary snow near the base of the snowpack makes large avalanches possible to trigger today. The snowpack has been slowly stabilizing since the mountains received 2-4 feet of snow last weekend, but we continue to get reports of unstable slopes. Yesterday in the southern Madison Range a snowmobiler triggered and was partially buried in an avalanche. They were not injured (<strong><a href="https://www.mtavalanche.com/node/24253">photos from Cabin Creek</a></strong>). Their group also remotely triggered two other slides. Skiers in the Bridger Range saw a slide occur from wind-loaded terrain near the ridge, uncertain whether it was skier or naturally triggered (<strong><a href="https://www.mtavalanche.com/node/24250">photo and info</a></strong>). On Thursday, two separate groups triggered large avalanches in the Lionhead area and near Big Sky (<a href="https://www.mtavalanche.com/images/21/lionhead-snowmobile-triggered-sli… photo</strong></a>, <a href="https://www.mtavalanche.com/images/21/remotely-triggered-slide-portal-1… Creek photo</strong></a>).</p>

<p>East winds yesterday and overnight drifted recent snow into fresh slabs that could break easily today, especially in the Bridger Range where wind was strongest. East winds are less common, and form slabs in unusual locations. These slabs are large enough to be harmful, and could trigger a much larger avalanche on sugary snow near the ground.</p>

<p>This season’s untrustworthy snowpack continues to show signs of instability and creates heightened avalanche danger. Today the avalanche danger is MODERATE. Carefully evaluate the snowpack and consequences of a slide before riding on or underneath steep slopes. As Ian indicated&nbsp;in his <strong><a href="https://www.youtube.com/watch?v=Zyj4LwxoEaU">video from Teepee Basin</a></strong> a few days ago, don’t let “stable” snowpack test results cause complacency. Remember recent human triggered slides as “unstable” test results.</p>

<p>Yesterday Doug snowmobiled north of Cooke City. In his <strong><a href="https://www.youtube.com/watch?v=7zv-hg9gzOI&amp;list=PLXu5151nmAvQDzKmH…; he mentions two types of terrain to be extra cautious of: 1) heavily wind-loaded slopes and 2) slopes with a relatively shallow snowpack (less than 4 or 5 feet deep). Be especially cautious of slopes that have both, heavy wind-loading on top of a shallow snowpack. Earlier in the week large natural avalanches broke on these types of slopes. This activity included a large avalanche on the south face of Mt. Abundance (<a href="https://www.mtavalanche.com/images/21/large-avalanche-mt-abundance"><st…;), a slide on Town Hill (<a href="https://www.mtavalanche.com/images/21/natural-avalanche-town-hill-cooke…;), slides low on Woody Ridge (<a href="https://www.mtavalanche.com/images/21/woody-ridge-avalanche-wide"><stro…;), and a large slide near Mt. Zimmer (<strong><a href="https://www.mtavalanche.com/images/21/natural-avalanches-near-zimmer">p…;). Yesterday, skiers south of Cooke City saw a recent natural avalanche on a heavily wind-loaded slope (<strong><a href="https://www.mtavalanche.com/node/24248">info</a></strong&gt;). Today, human triggered avalanches are possible and the avalanche danger is MODERATE. Carefully evaluate snowpack and terrain before riding steep slopes, and allow no more than one person at a time on or underneath steep 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>