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Two wet slabs that looked to have released during the past 48 hours. The smaller slide on the left had a debris pile that was 6' deep. The larger slide on the right failed at the ground and took most of the snow in the chute with it. The large slide may have been triggered from smaller loose wet slide that was set off by a skier. Photo: A. Schauer

Avalanche Details: Wet avalanche activity in the Bridgers
Forecast link: GNFAC Avalanche Forecast for Fri Mar 22, 2019GNFAC Avalanche Forecast for Sat Mar 23, 2019
Bridger Range, 2019-03-21
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    • GNFAC Avalanche Forecast for Thu Mar 21, 2019

    Snowpack and Avalanche Discussion

    <p>Conditions are changing rapidly and the snowpack is starting to fall apart. Yesterday there were many wet avalanches reported. Eric was in Beehive Basin and saw multiple wet loose slides and (<strong><a href="https://www.mtavalanche.com/images/19/point-release-beehive-basin">phot…;) and got a good look at some wet slabs from the highway (<strong><a href="https://www.mtavalanche.com/images/19/wet-slab-gallatin-canyon">photo</…;). Skiers north of Cooke City saw similar conditions (<strong><a href="https://www.mtavalanche.com/images/19/many-wet-loose-avalanches">photo<…;). Cornices are weakening and sagging and are effective triggers to both wet and dry avalanches (<strong><a href="https://www.mtavalanche.com/images/19/cornice-fall-and-small-avalanche"…;, <a href="https://www.mtavalanche.com/images/19/cornice-failure-beehive-basin">ph…;).</p>

    <p>Above freezing temperatures and intense sunshine has wet the snowpack. On slopes where the snow is shallow and weak the melt-water will quickly create instability. Most mountain ranges froze last night, and even in the Bridger Range and Hyalite which had temperatures in the 30s, the snow surface will be frozen. After a few hours of morning sun the crust will melt and avalanche activity will increase. Cornices may break, wet point release slides will become numerous, and a few deep wet slabs will avalanche. Most of this action will occur on southerly facing slopes where solar input is greatest. If you start crashing to the ground in wet snow you know you overstayed your welcome and need to hurry home.</p>

    <p>During Eric’s tour in Beehive Basin he had concerns regarding wet and dry snow. He backed off his plan to ski a high elevation north facing slope when he saw large cornices and obvious wind-loading from the ridgeline (<strong><a href="https://www.youtube.com/watch?v=W4q4NdCfmX8&amp;list=PLXu5151nmAvRNl9ku…;). In Bacon Rind on Tuesday I found southerly facing slopes quickly deteriorating from the warm temperatures and got easy fractures in my stability tests (<strong><a href="https://www.youtube.com/watch?v=O_M2PnMldm0&amp;list=PLXu5151nmAvRNl9ku…;). Throughout the forecast area, snowpack structure and stability is changing quickly for the worse during the warm daylight hours. For today, the avalanche danger will start <strong>LOW</strong>, but become <strong>CONSIDERABLE</strong> by midday on slopes that get wet.</p>

    <p>If you get out and have any avalanche or snowpack observations to share, contact us via our <u><a href="https://www.mtavalanche.com/node/add/snow_observation">website</a></u&gt;, email (<u><a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a></u&gt;), phone (406-587-6984), or Instagram (#gnfacobs).</p>

    Wet slab avalanches will be a growing concern as free moving water travels through the snowpack. This problem is most likely on mid to low elevation slopes that have a shallow snowpack and poor structure. Be aware of wet slabs as temperatures warm and the snowpack becomes increasingly unstable. Photo: GNFAC 


    Forecast link: GNFAC Avalanche Forecast for Thu Mar 21, 2019
    Northern Madison, 2019-03-20
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