From obs: "Skied Mount Blackmore today (3/27/21)... around 1 pm a skier remote triggered a deep slab from ~50 feet away (around the corner lookers right in the attached picture). Broke at the ground, 10-15feet deep, and took out a small tree." Photo: M. Lavery
From obs: "Skied Mount Blackmore today (3/27/21). Saw a natural avalanche on Alex Lowe peak just south of the Hellmouth...". Photo: M. Lavery
From obs: "Skied Mount Blackmore today. Saw... 4 skier triggered slides on the E face between the Blackmore and Alex Lowe Basins. Most appeared to be wind slabs... " Photo: M. Lavery
From obs: "We were skinning up Pyramid Point from the East. as we approached 10,000 ft, we encountered a wind slab on an East Facing slope. it was about 1-2 inches where we encountered it but it quickly propogated. the crown was 18-20 inches at its highest and about 150 feet wide. the debris ran for about 200 feet."
From obs (3/27/21): "We were skinning up Pyramid Point from the East. as we approached 10,000 ft, we encountered a wind slab on an East Facing slope. it was about 1-2 inches where we encountered it, but it quickly propogated. the crown was 18-20 inches at its highest and about 150 feet wide. the debris ran for about 200 feet."
Small snowmobile triggered slide in the new snow on Buck Ridge. Likely triggered on 3/26/2021. Photo taken 3/27.
Photo: GNFAC
<p>Strong winds have drifted recent snow into deep drifts that can break under the weight of a skier or rider today. Alex was in the northern Bridger Range yesterday and identified these drifts as the chief concern going into the weekend (<a href="https://www.youtube.com/watch?v=azSnzDUAG18"><strong><u>video</u></stro…;). A small skier triggered wind slab near Big Sky yesterday is an example of what to look out for today and the sort of terrain where triggering a slide could be particularly hazardous (<a href="https://www.mtavalanche.com/images/21/wind-slab-middle-basin"><strong><…;). Pay attention to the texture of the snow surface for visual clues to identify these drifts. Look for drifted pillows near ridgelines, beneath cornices, and downwind of trees or rocks. If you feel the snow surface stiffening under your feet, you’ve found one of these drifts and should stop to assess before proceeding into steep terrain. These drifts will be particularly deep and easy to trigger in areas near Big Sky with the biggest overnight snow totals. </p>
<p>On some slopes, beneath the recent snow is a thin layer of weak snow (called near-surface facets) that makes for a poor bond to the old snow surface. The distribution of this weak layer is spotty. Near Cooke City it appears to primarily be on west facing slopes, but that pattern doesn’t hold in other areas (<a href="https://www.youtube.com/watch?v=CZ27CVuKWuA"><strong><u>Cooke video</u></strong></a>). Assume it’s on every slope until you prove otherwise by digging to look for it. There is also a small possibility that avalanches breaking in the upper snowpack could step down to the weak layers at the ground.</p>
<p>The strong spring sun is supposed to come out this afternoon, which in many places will moisten the new snow for the first time. Watch for the snow surface getting sticky and cohesive, with roller balls and pinwheels being clear signs that the conditions for loose snow avalanches are developing. Move to shadier slopes or out of steep terrain to avoid this issue. </p>
<p>Large avalanches are possible and the avalanche danger is MODERATE today.</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>
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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:
March 29, 6 p.m., Free 1-Hour Avalanche Awareness, online Link to Join HERE
Observation from Electric Peak on 3/26/21.
From obs: "...I did get one small slab to pull on the crust layer on an E aspect at 8000’, so the snow has proven to not be uniformly well-bonded..."
Photo: S. Reinsel
From obs: "On Friday, my partner and I went into Middle Basin with the objective of skiing Middle Peak, and possibly the short couloir that splits the face. That morning we dug a pit on the east facing aspect of the beehive/middle basin ridge (ECTx). Encouraged by our results, we continued on to the base of middle peak and dug another pit (ECTp 30) on the south-facing ice crust. We continued on to summit middle peak and ski down the face to the entrance of the couloir , we descended 20ft into the entrance on soft loose snow and dug our third pit (ECTx), we replicated our results and decided the feature would be safe to ski. At ~1pm the first skier descended the slope, and triggered a small windslab (4-8in and 20ft wide) about 100ft down the slope and skied away uncaught. Skier 2, descended a lower angle slope to the east."
