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<p>The mountains near Cooke City received over 4 feet of snow equal to 4” of snow water equivalent (<a href="https://www.nrcs.usda.gov/wps/portal/nrcs/detail/or/snow/?cid=nrcs142p2…;) between Wednesday and Saturday. This rapid, heavy load and strong wind resulted in widespread natural and human triggered avalanches 2-4’ deep. Many of these slides were observed yesterday as visibility cleared. See our <strong><a href="https://www.mtavalanche.com/photos">photos page</a></strong> or <strong><a href="https://www.mtavalanche.com/advisory/cooke-city">regional page</a></strong> for a look at all the activity, or our <strong><a href="https://www.mtavalanche.com/weather/wx-avalanche-log">weather and avalanche log</a></strong> for a list of recent avalanches.</p>

<p>These slabs will quickly gain strength on many slopes, but today large avalanches 2-4’ deep are easy to trigger, especially on wind-loaded slopes. On slopes where the snowpack is relatively shallower, a layer of facets 3-4 feet deep can produce large avalanches even without a wind load. Avalanche danger today is <strong>CONSIDERABLE</strong>. Avoid wind loaded slopes and be extra cautious on or below avalanche terrain.</p>

<p>In the Lionhead area near West Yellowstone a weak and unstable snowpack was pushed to its breaking point by a few inches of snow last week. On Thursday, Doug observed multiple natural avalanches in this area (<a href="https://www.youtube.com/watch?v=85UQeqSWXqk&amp;list=PLXu5151nmAvQSYtIf…;, <strong><a href="https://www.mtavalanche.com/images/17/looking-avalanche-crown">photo</a…;). These slides broke on sugary, weak facets&nbsp;buried 2-3’ deep on all aspects and elevations (<a href="https://www.mtavalanche.com/images/17/lionhead-crown"><strong>photo</st…;). This widespread layer of&nbsp;weak facets makes large avalanches easy to trigger today. Under these conditions, avalanches can be triggered remotely from flat terrain or low angle terrain below. The avalanche danger today is <strong>CONSIDERABLE</strong>. Avoid wind-loaded slopes and be extra cautious on and below all steep slopes.</p>

<p>The mountains near Bozeman and Big Sky got 2-3 feet of snow equal to 2-3” of snow water equivalent (<a href="https://www.nrcs.usda.gov/wps/portal/nrcs/detail/or/snow/?cid=nrcs142p2…;) between Tuesday and Saturday. Strong wind yesterday drifted this snow into slabs 2-3’ deep that are easy to trigger today. Natural and snowmobile triggered avalanches were observed on Buck Ridge<strong> </strong>yesterday (<strong><a href="https://www.mtavalanche.com/images/17/remote-triggered-slide-buck-ridge…;, <strong><a href="https://www.mtavalanche.com/images/17/natural-slab-mcatee-basin">photo<…;) and in Tepee Creek on Friday (<a href="https://www.mtavalanche.com/images/17/snowmobile-triggered-slide-tepee-…;, <a href="https://www.mtavalanche.com/images/17/natural-avalanche-tepee-creek"><s…;). On slopes with a relatively shallow snowpack, weak facets 2-3’ deep produced natural avalanches and widespread cracking and collapsing. Eric found this bullseye instability data near Bacon Rind on Friday (<a href="https://youtu.be/iEGue4T9rzo"><strong>video</strong></a&gt;, <a href="https://www.mtavalanche.com/images/17/avalanche-road-cut-191"><strong>p…;), and I found it near Big Sky (<strong><a href="https://youtu.be/uyHF7iKRjtM">video</a></strong&gt;).</p>

<p>Doug and I went to the west side of the Bridger Range yesterday to look at an avalanche that caught and injured a skier on Friday (<strong><a href="https://youtu.be/7ETCg89ANx0">video</a></strong&gt;, <strong><a href="https://www.mtavalanche.com/images/17/truman-gulch-crown-skier-triggere…;). The slide broke 2 feet deep on old, weak faceted snow. This is bullseye data that some slopes are unstable and recent snow and wind pushed them to a breaking point. Travel in avalanche terrain today requires careful snowpack evaluation and cautious route finding. Recent snow and strong wind make avalanches easy to trigger today and avalanche danger is <strong>CONSIDERABLE</strong>.</p>

<p>If you get out and have any avalanche or snowpack observations to share, drop a line via our <a href="https://www.mtavalanche.com/node/add/snow_observation">website</a&gt;, email (<a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a&gt;), phone (406-587-6984), or Instagram (#gnfacobs).</p>