24-25

<p><span><span><span><span><span><span>Intense snowfall with moderate wind will create dangerous avalanche conditions, and large human-triggered avalanches are likely. Snow stability will get worse through the day, especially on wind loaded slopes where natural avalanches are likely during the storm.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>The snowpack has weak layers of sugary facets and surface hoar buried 1-3’ deep which showed signs of instability over the last couple days, including a </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/32662"><span><span><span><strong><span… report</span></span></u></span></strong></span></span></span></a><span><span><span><strong><span><span> </span></span></strong></span></span></span><span><span><span><span><span><span>of a snowmobile triggered avalanche that partially buried a rider near Lionhead (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=01zVyy8U8D8&amp;list=PLXu5151nmAvToI_ir… 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://youtu.be/4xSA_C9cPuc?feature=shared"><span><span><span><strong>… Park 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.youtube.com/watch?v=FKh0OZ-BnUs"><span><span><span><strong>… Rind video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). </span></span></span></span></span></span><span><span><span><strong><span><span>Persistent slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> breaking on this weak layer can break hundreds of feet wide and can be triggered from lower angle terrain connected to slopes steeper than 30 degrees.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Choose terrain that is less than 30 degrees steep, and not connected to or below anything steeper. Be extra cautious of steep wind-loaded slopes, and avoid crossing or sitting in runout zones below. The avalanche danger is HIGH on wind-loaded slopes and CONSIDERABLE on all other slopes near Island Park, West Yellowstone and in the southern Madison and Gallatin Ranges.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Heavy snowfall and moderate wind will cause the avalanche danger to rise through the day. A person can trigger </span></span></span></span></span></span><span><span><span><strong><span><span>wind slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> that easily break within fresh drifts that form today. These can be large enough to bury a person, especially near Cooke City where more snow has fallen over the last week (18” = 1.8”SWE) and more is expected today.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Additionally, </span></span></span></span></span></span><span><span><span><strong><span><span>persistent slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> could break deeper on weak layers buried 1-3’ deep. While there has been less signs of instability recently in these areas, snowfall has been slowly adding weight over the last week, and today’s intense snowfall and wind could finally overload the strength of these weak layers (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=P6thCGML-1s&amp;list=PLXu5151nmAvToI_ir… City 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.youtube.com/watch?v=yuTTHqltBiw"><span><span><span><strong>… video</span></span></u></span></strong></span></span></span></a><span><span><span><strong><span><span>, </span></span></strong></span></span></span><a href="https://www.mtavalanche.com/node/32650"><span><span><span><strong><span… media and observation</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Avalanches on persistent weak layers are less predictable, and can break after multiple people cross a slope, and without obvious signs of instability. If you have any doubt about snowpack stability, steer clear of steep slopes and runout zones below.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Practice conservative decision making today, and choose routes that avoid wind-loaded slopes steeper than 30 degrees. Human triggered avalanches are likely, especially on wind-loaded slopes, and the avalanche danger is CONSIDERABLE near Bozeman, Big Sky and Cooke City.</span></span></span></span></span></span></p>