Snowpack and Avalanche Discussion
<p><span><span><span><span><span><span>Heavy snowfall overnight and continued heavy snowfall today mean that natural and human triggered avalanches are both likely. Avalanches may break within the new snow or on the weak layers buried 2-4 ft deep (deeper in windloaded areas). Warming temperatures overnight mean the new snow is falling “upside down” (denser over less dense), which makes </span></span></span></span></span></span><span><span><span><strong><span><span>Storm Slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> within the new snow especially likely. Avalanches will be bigger and even easier to trigger on windloaded slopes.</span></span></span></span></span></span></p>
<p><span><span><span><strong><span><span>Persistent Slab avalanches </span></span></strong></span></span></span><span><span><span><span><span><span>breaking deeper in the snowpack on the early December weak layers are the wild card that really worry me today. During the last round of snow, there were big natural avalanches on </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/33142"><span><span><span><span><span><… Mountain</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span> and </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/33267"><span><span><span><span><span><… Peak</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>. With rapid loading of the weak layers, I expect more of these big slides today. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Be very cautious if you get out today. Stay off and out from under all steep slopes. Low visibility will make it hard to tell how close you’re getting, so give yourself a wide margin. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>The avalanche danger is HIGH on all slopes.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Steady snowfall over the last ten days has kept the snowpack teetering on the edge. It’s snowing again and you could easily trigger a large </span></span></span></span></span></span><span><span><span><strong><span><span>Persistent Slab avalanche</span></span></strong></span></span></span><span><span><span><span><span><span> on weak layers buried 1-3 ft deep (and deeper in windloaded areas). We continue to get feedback from the snowpack via collapsing, whumpfs, and avalanches (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/snow-observations-list"><span><span><span><… out our observations page</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span> to view the latest reports with all these red flags). New snow today will make these easier to trigger.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Winds have generally been light since snowfall began, so there is still plenty of soft snow available to blow around. Yesterday, the Big Sky Ski Patrol found sensitive wind slabs after the winds picked up just a little bit. Be on the lookout for fresh wind drifts where you could trigger a </span></span></span></span></span></span><span><span><span><strong><span><span>Wind Slab avalanche</span></span></strong></span></span></span><span><span><span><span><span><span> today. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Decision making should be pretty simple today - it’s snowing, weak layers are getting loaded, and avalanche conditions are dangerous. There is powder everywhere, so go out and enjoy it on slopes less than 30 degrees steep. The steep slopes will still be there when it stops snowing and conditions stabilize.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>The avalanche danger is CONSIDERABLE today.</span></span></span></span></span></span></p>
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