We saw this natural avalanche on 3/19/22 appeared to be within 24 hours old and triggered by cornice fall that broke out a slab below. Northeast aspect at 8,800' on Lionhead Ridge. Photo: GNFAC
We saw this natural avalanche on 3/19/22 appeared 24-48 hours old and triggered by cornice fall that broke out a slab below. North aspect at 10,000' behind the top of Targhee Creek near Lionhead. Photo: GNFAC
<p>Today a person can trigger avalanches that break 1-3 feet deep. Over the last week we have seen that recent new and wind-drifted snow created an unstable slab over weak layers in the upper snowpack (<a href="https://youtu.be/92V-3sb_6R0"><strong>Buck Ridge video</strong></a>). Yesterday near Cooke City, skiers and riders reported a couple recent large natural avalanches (<strong><a href="https://www.mtavalanche.com/node/26259">photo and details</a></strong>, <strong><a href="https://www.mtavalanche.com/node/26249">details</a></strong>), and a skier triggered avalanche that broke a foot deep (<strong><a href="https://www.mtavalanche.com/images/22/skier-triggered-slide-mount-abund…;). All were large enough to bury or injure a person and examples of the type of slide that is possible today.</p>
<p>Throughout the forecast area weak layers are buried less than a couple feet deep, and you can easily dig down to see if they exist and create an unstable snowpack. Near Cooke City, there are additional weak layers buried around 3 feet deep that could cause larger slides. Avoid steep slopes where a stiff slab rests on top of sugary, weak snow or a hard crust, or worse, both weak snow and a hard crust. Avalanches breaking on these weak layers can be large and deadly, and can be triggered from flatter terrain below or adjacent to steep slopes (<a href="https://youtu.be/f6wLR3tLNa8"><strong>Wyoming Bowl video</strong></a>, <a href="https://www.mtavalanche.com/node/26199"><strong>Mt. Blackmore slide details</strong></a>).</p>
<p>Temperatures will rise above freezing in most areas today and make wet snow avalanches possible. Increasing southwest-west wind could blow snow into small fresh drifts that could break and avalanche under the weight of a person. Both of these types of avalanches will probably be small, but worth watching out for, especially in terrain where a small slide would be deadly if it pushed you over cliffs, rocks or into trees.</p>
<p>If you plan to ride, ski, climb or any sort of travel on steep slopes, carefully assess the snowpack for instabilities and evaluate terrain for the consequences of being caught in an avalanche. Today, large avalanches are possible to trigger, and the avalanche 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>
From obs. 3/18/22: "Slide which looks to be triggered by a skier or snowboarder, on an east facing slope of Mount Abundance. Slide pictured was estimated 100 feet wide, and 12" deep, and ran a couple hundred feet. If you look to the right, on the slope, another crown can be seen, which was equal size to this one."
From obs. 3/18/22: "Slide which looks to be triggered by a skier or snowboarder, on an east facing slope of Mount Abundance. Slide pictured was estimated 100 feet wide, and 12" deep, and ran a couple hundred feet. If you look to the right, on the slope, another crown can be seen, which was equal size to this one." Photo: R. DeSilva
From obs. 3/18/22: "Slide Observed on North Face of Crown Butte. Possibly a cornice collapse." Photo: R. DeSilva
From obs. 3/18/22: "Slide observed on Miller mountain, on a NE face." Appears a couple days old. Photo: R. DeSilva
