Lots of collapsing today near Miller Ridge (S, SE facing slopes), just 50' from the road. This continued in more sheltered areas as well. Dug on a NE facing slope at 9300', HS: 80 ECTP12 @ 40 cm.
NE aspect 7600 ft.
Hand pit - 40 cm deep
First 15cm of the snowpack from the ground up, was rotten, un-compacted snow, with a thin hard crust.
Top 25 cm was compacted snow, density 4F.
S Brackett Cr road has a few inches over most of it. Snowpack is still too shallow to allow for much skiing.
<p><span><span><span><span><span><span>The mountains throughout the forecast area have dangerous avalanche conditions due to 1-2 feet of snow over the last week falling on a weak snowpack (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/weak-snow-found-tepee-basin"><spa…;). Human-triggered avalanches are likely today. Yesterday Doug and I went to Beehive Basin and easily got the snowpack to collapse when breaking trail, and we saw a poor snowpack structure similar to elsewhere in the forecast area (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=AUqVL5Fo0eM&list=PLXu5151nmAvSH326z…;, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/weak-and-unstable-snow-beehive"><…;).</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Over the weekend we got reports of human triggered avalanches, natural avalanches and widespread collapsing and whumphing of the snowpack, showing the current high potential to trigger an avalanche. Notable recent signs of a dangerous snowpack include (but not limited to):</span></span></span></span></span></span></p>
<ul>
<li><span><span><span><span><span><span>On Saturday a skier triggered and was not caught in an avalanche at Bridger Bowl in terrain that is currently the backcountry (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/skier-triggered-avalanche-super-c…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>Riders remotely triggered avalanches in Tepee Basin (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/remote-triggered-slide-tepee"><sp…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>Natural avalanches were reported in Beehive Basin (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29458"><span><span><span><strong><span…;), Taylor Fork (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29455"><span><span><span><strong><span…;), Cooke City (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/avalanche-henderson-mtn"><span><s…;) and on Elephant Mtn. in Hyalite (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29474"><span><span><span><strong><span…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>Skiers, riders and ice climbers had large collapses of the snowpack near West Yellowstone (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29454"><span><span><span><strong><span…;), Hyalite (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29460"><span><span><span><strong><span…;), Cooke City (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29430"><span><span><span><strong><span…;), the Bridger Range (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29415"><span><span><span><strong><span…;), Big Sky (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29449"><span><span><span><strong><span…;) and the southern Madison Range (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29476"><span><span><span><strong><span…;).</span></span></span></span></span></span></li>
<li><span><span><span><span><span><span>Find more info in our field videos from the last week from Beehive, Bridger, Hyalite, Island Park, Cooke City and Lionhead (</span></span></span></span></span></span><a href="https://www.youtube.com/playlist?list=PLXu5151nmAvSH326zVaU9KXJAPtvkIt-…;), and browse the many </span></span></span></span></span></span><a href="https://www.mtavalanche.com/snow-observations-list"><span><span><span><… observations</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span> on our website.</span></span></span></span></span></span></li>
</ul>
<p><span><span><span><span><span><span>Today a person can easily trigger an avalanche on steep slopes and terrain connected to steep slopes. Slopes that did not have snow on the ground prior to last week have better stability, but to identify these areas you must be diligent with snowpack assessment, and other early season hazards are more prevalent due to a shallower snowpack (rocks, logs, etc.). The best plan is to avoid travel on and underneath slopes steeper than 30 degrees. Additionally, recent strong winds drifted snow into thicker slabs, so wind-loaded slopes are especially dangerous (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/23/windy-bridgers"><span><span><span…;).</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Throughout the forecast area, human triggered avalanches are likely and the avalanche danger is CONSIDERABLE.</span></span></span></span></span></span></p>
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.
From email: "I dug a pit in the normal location to check the snow pack conditions and here’s what I found.
Aspect: East
Slope Angle: 19
Elevation: 8100ft
Total pit depth 70cm
Winds: light 5mph with gusts up to approximately 15mph. I wasn’t on the very top of the ridge so I was a little protected.
ECTP 22 The failure was right at the old snow and new snow line 27cm up from the ground.
The snow coverage of the parking lot, trail up and off trail areas wasn’t great, but I’ve seen worse."
1 team yesterday (Saturday, not me) climbed Bobo Like and Big Sleep (first 2 pitches of each). They experienced 2x collapses but no other signed of instability.
Got ECTP10/11 in a pit on an east facing slope at 9100'. The snowpack is about 60cm deep, with 30cm of facets and 30cm of fist to 4 finger hardness new snow . The test failed at the interface of the old facets and new snow.
We decided to keep the skiing to below 30 degrees. After skiing one slope and skinning back up, we noticed widespread cracking around our ski tracks (image), but luckily the terrain was mellow enough that nothing moved.
Climbers in Hyalite saw a large natural avalanche on Elephant Mountain. 12/10
