<p>We’re now four days out from the last significant snowfall. But that snowfall was a big one, with 2-4 ft of snow accumulating during the storm. Strong winds after the storm drifted the new snow around and continued loading the snowpack on many slopes through the first half of the week. During the storm there were widespread natural avalanches (<a href="https://youtu.be/MyCLaNW0eUU"><strong><u>Bridger Range video</u></strong></a>, <a href="https://www.youtube.com/watch?v=MowctT2PVAE"><strong><u>Buck Ridge video</u></strong></a>, <a href="https://www.mtavalanche.com/images/21/large-avalanche-skyline-ridge"><s… Skyline Ridge avalanche photo</u></strong></a>). The snowpack is no longer hair-trigger, but triggering avalanches remains very much a possibility. Yesterday, snowmobilers in Portal Creek remotely triggered two large avalanches that broke on weak snow near the ground (<a href="https://www.mtavalanche.com/node/24219"><strong><u>details and photos</u></strong></a>). Thankfully no one was caught.</p>
<p>In Teepee Basin yesterday, I saw numerous natural avalanches that broke during the storm, but didn’t get the weak layers to break in my snowpack tests (<a href="https://www.youtube.com/watch?v=Zyj4LwxoEaU"><strong><u>video</u></stro…;). I still kept off steep slopes because recent avalanche activity is clear evidence that the snowpack has been pushed past its breaking point and the weak layers in the bottom half of the snowpack will take a while to heal, despite mixed signals from snowpack test results. While the likelihood of triggering a slide is slowly decreasing, the consequences aren’t diminishing. Stay diligent and keep making conservative terrain choices.</p>
<p>The avalanche danger is MODERATE.</p>
<p> </p>
<p>Cooke City saw 3-4 feet of snow during the last storm and strong winds at all elevations out of many directions. Numerous natural avalanches were reported following the storm, including a very large one on the south face of Mt. Abundance (<a href="https://www.mtavalanche.com/images/21/large-avalanche-mt-abundance"><st…;), on Town Hill (<a href="https://www.mtavalanche.com/images/21/natural-avalanche-town-hill-cooke…;), and slides that propagated widely, low on Woody Ridge (<a href="https://www.mtavalanche.com/images/21/woody-ridge-avalanche-wide"><stro…;). Triggering a large avalanche on buried weak layers remains possible today, particularly on wind-loaded slopes. Watch for drifts in unusual places on low elevation slopes as well as the usual areas around ridgelines. The danger is rated MODERATE. </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>
See our education calendar for an up-to-date list of all local classes. Here are a few select upcoming events and opportunities to check out:
From email on 2/11: "interesting Av. activity in a Central Park - mid-lower Woody. This is an area that cross-loads like crazy, so it's not surprising to see slides, but the extent was impressive; essentially, slides propagated across the entire zone. These are all mid-slope ~9,000-9,200'"
Likely broke following the wind event on 2/9/2021.
From email on 2/11: "interesting Av. activity in a Central Park - mid-lower Woody. This is an area that cross-loads like crazy, so it's not surprising to see slides, but the extent was impressive; essentially, slides propagated across the entire zone. These are all mid-slope ~9,000-9,200'"
Photo: J. Logan
From email on 2/11: "interesting Av. activity in a Central Park - mid-lower Woody. This is an area that cross-loads like crazy, so it's not surprising to see slides, but the extent was impressive; essentially, slides propagated across the entire zone. These are all mid-slope ~9,000-9,200'"
Photo: J. Logan
Multiple large natural avalanches ran on Skyline Ridge, on the side facing Cabin Creek and the side facing Teepee/Bacon Rind Creeks. They likely broke during the avalanche warning on Sunday, Feb 7th. One slide on the Cabin Creek side of the ridge ran within 300 ft of the Big Sky Trail. Many of the slides appear to have broken on weak layers near the ground.
A large avalanche that broke on Skyline Ridge and ran within 300 ft of the Big Sky Trail. Likely broke on Sunday, Feb 7th.
Photo: B. Ramage
Debris from a large avalanche that broke on Skyline Ridge and ran within 300 ft of the Big Sky Trail. Likely broke on Sunday, Feb 7th.
Photo: B. Ramage
On Thursday, Feb 11, snowmobilers remotely triggered two large avalanche in the Portal Creek area.
From obs: "Broke on lookers right crown first then triggered second slide to lookers left (rocks everywhere). Broke on depth hoar on both slides north facing aspects. Nobody was caught."
