Patrollers at the Yellowstone Club spotted a natural avalanche under the cliffs to the looker's right on Cedar Mountain. It likely failed during or immediately after this weekend's snowstorm (March 20th). Photo: YCSP
A snow surfer reported many natural avalanches breaking in the Divide Cirque running from wind-loaded terrain near ridgelines most of the length of the slopes. Avalanches failed at or near the interface with the 12" of snow from this weekend.
A skier triggered an avalanche mid-slope on Saddle Peak in the Bridger Range early afternoon March 21st. Thankfully the individual was able to ski out of the slide.
A skier triggered an avalanche mid-slope on Saddle Peak in the Bridger Range early afternoon March 21st. Thankfully the individual was able to ski out of the slide. Photo: G. Turnage
From obs: "2 ski cuts in the top of the bowl and it ran most of the way to the bottom. Skiing next to the path, 4 turns would generate enough sluff that you had to get out of the way. No slab releases but the sluff could knock you down if you weren’t looking out for it."
<p>The 48-hour storm total in the mountains around Bozeman and Big Sky is 6-10” equal to 0.6-0.8” of snow water equivalent (<a href="https://www.nrcs.usda.gov/wps/portal/nrcs/detail/null/?cid=nrcseprd1314…;) with 2-5” (0.2-0.3” SWE) near West Yellowstone and Cooke City. Winds remained light through the storm, exceptions to this are periods of moderate winds in the Bridger and North Gallatin Range and the mountains near Cooke City.</p>
<p>With higher storm totals, new snow avalanches will be deeper and more dangerous near Bozeman and Big Sky. Skiers in Hyalite Canyon and the Beehive Basin area saw natural avalanches that failed yesterday below the new snow (<a href="https://www.mtavalanche.com/node/26282"><strong>Hyalite photo and details</strong></a><strong>, </strong><a href="https://www.mtavalanche.com/node/26281"><strong>Beehive details</strong></a>). The Big Sky Ski Patrol reported the storm snow was “extremely sensitive” to triggers. This weekend’s snow remains a concern today. Additionally, as temperatures climb this afternoon, the recent snow will be more likely to slide on slopes getting hit by the spring sun.</p>
<p>Slopes across the advisory area with recent drifts of wind-loaded snow are suspect. Yesterday, the Bridger Bowl Ski Patrol noted that the wind was rapidly forming slabs near ridgelines and under cliffs that readily broke 6-18” deep. This weekend sections of cornice broke and triggered avalanches near Lionhead (<a href="https://www.youtube.com/watch?v=xc770oqXMsE&list=PLXu5151nmAvT1nrM2…;, <a href="https://www.mtavalanche.com/node/26265"><strong>photos and details</strong></a>) and in the Republic Creek drainage (<a href="https://www.mtavalanche.com/node/26275"><strong>photo and details</strong></a>). Last week, similar avalanches failed on <a href="https://www.mtavalanche.com/node/26230"><strong>Saddle Peak</strong></a>, <a href="https://www.mtavalanche.com/node/26195"><strong>Buck Ridge</strong></a> and <a href="https://www.mtavalanche.com/node/26199"><strong>Mount Blackmore</strong></a>. Treat slopes commonly loaded by the wind and near ridgelines with added caution.</p>
<p>Large avalanches are possible due to persistent weak layers buried 1-3’ deep on many slopes. On Saturday, skiers in Bear Basin made a hasty retreat after they triggered an audible collapse in the snowpack (<a href="https://www.mtavalanche.com/node/26274"><strong>details</strong></a>). Last week, natural avalanches broke on Crown Butte and Miller Mountain, skiers triggered a slide near Mount Abundance and a natural avalanche broke an estimated 1,000’ wide on Cedar Mountain. See these and all reported avalanche activity on our <a href="https://www.mtavalanche.com/avalanche-activity"><strong>activity log</strong></a>.</p>
<p>This adds up to tricky avalanche conditions. Many slopes are stable, similar to what Doug and I found at the Throne yesterday (<a href="https://www.youtube.com/watch?v=6UH-zaFfU3c"><strong>video</strong></a&…;), but safe travel in and around avalanche terrain requires thorough snowpack assessments and a willingness to heed warning signs if you observe indicators of instability. Human-triggered avalanches are possible, and the danger is MODERATE.</p>
<p>If you get out, please send us your observations no matter how brief. You can submit them via our website, email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).</p>
Small (R1) storm slabs were observed under a cliff band at the mouth of Middle Basin
