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<p><span><span><span><span><span><span>Snow that fell last week was drifted into stiffer slabs on top of a very weak snowpack, and these slabs remain easy for a person to trigger (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/24/surface-hoar-stripe-underneath-sl… photo</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/24/large-buried-surface-hoar-layer">…;, </span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=K_t6Fi6wUC4&amp;list=PLXu5151nmAvSH326z… of weak layers</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Last week there were natural and human triggered avalanches mid-week during the peak of snowfall and wind (Cooke City </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29906"><span><span><span><strong><span…;, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29921"><span><span><span><strong><span…;, Big Sky </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29873"><span><span><span><strong><span…;), and skiers and riders triggered avalanches on Thursday and Friday (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=aTnE5gzG1sc"><span><span><span><strong>… Fork video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29915"><span><span><span><strong><span… City photos</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). On Saturday skiers near West Yellowstone observed large collapses with shooting cracks (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29935"><span><span><span><strong><span…;), and yesterday a rider south of there saw a recent human-triggered avalanche (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29941"><span><span><span><strong><span…;).</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>A couple inches of new snow and increased wind overnight added weight to unstable slabs. Although this was a small loading event, everything counts with the current very weak snowpack. On wind-loaded slopes human triggered avalanches are likely. Many recent avalanches were triggered remotely, from a distance (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/avalanche-activity"><span><span><span><stro… activity</span></span></u></span></strong></span></span></span><span><span><span><span><span><u><span><span> </span></span></u></span></span></span></span></span><span><span><span><strong><span><u><span><span>list</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>), meaning you could trigger a slope from lower angle terrain adjacent to or below steeper slopes. Persistent weak layers are tricky, especially as stability improves with time since a larger loading event. A slope might allow multiple tracks before it breaks, and stability test results will be more variable. Any slope with a cohesive, supportable slab on top of weak, sugary snow has the potential to avalanche.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>On slopes that do not have previous wind-loading, slabs of snow are softer and less likely to break wide, but a few slopes could have just enough structure to be unstable. On sustained, steep slopes dry loose avalanches can become large due to entraining the very weak snowpack as a “facet slough” (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=Y0LROtnc7Us"><span><span><span><strong>… Ridge video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>).</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Careful snowpack evaluation and cautious route finding are required today. Be cautious of travel on or below slopes steeper than 30 degrees, especially previously wind-loaded slopes. Avalanche danger is CONSIDERABLE on wind-loaded slopes and MODERATE on non-wind loaded slopes. </span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>In the Bridger Range avalanches are possible to trigger where recent snow was drifted into slabs on top of a very weak snowpack (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=GJxMtiIQGbs"><span><span><span><strong>… Range video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Watch and feel for signs of wind drifting, such as cracking across the snow surface, cornices, or smooth rounded pillows of snow. Avoid steep slopes that have these signs. The weak snowpack can also cause facet sluffs that gouge deep into the snowpack and run long distances (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=Y0LROtnc7Us"><span><span><span><strong>… Ridge video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Be cautious of long, sustained steep slopes where these may occur, especially if there are consequences like rocks, trees or cliffs. Carefully evaluate the snowpack and consequences of an avalanche before traveling on or below steep slopes. The avalanche danger is MODERATE.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>The cold temperatures create higher consequences of an accident, and any bad situation can quickly become worse.</span></span></span></span></span></span></p>