19-20

<p>Yesterday marked the second day in a row without avalanche activity. The last 2 day spell without avalanches was December 23^rd, 31 days ago, and during that time we’ve had snowfall somewhere in our forecast area on 26 of those days. It’s been an active season with avalanches getting deeper and larger as snow accumulates (<strong><a href="https://www.mtavalanche.com/weather/wx-avalanche-log">Weather and Avalanche Log</a></strong>).</p>

<p>Our mountains have a common problem: weak, sugary facets near the ground are avalanching. Avalanches have been unusually large and breaking 5-15’ deep in areas that are wind-loaded. The slides have been piecemeal with one here and one there, making it difficult to determine which slopes are safe and which are not. Typically we see signs of instability like cracking or collapsing that warn us of danger, but with these deeper slides there is no warning, it just avalanches. Consequently, the other forecasters and I are being conservative in our route choices, even though the likelihood of triggering slides is decreasing. We just don’t trust the snowpack, and neither should you.</p>

<p>We try and investigate as many of these slides as possible, especially those that are human triggered. Yesterday, Dave skied up Flanders Creek in Hyalite to look at two large slides, one 7’ deep that was triggered on Saturday by 2 skiers (<strong><a href="https://youtu.be/HLWnHKAslnM">video</a></strong&gt;). The story will be familiar to regular readers of the forecast. A thick slab of windblown snow was triggered from a thinner part of slope when the skier’s weight collapsed the weak layer. This last sentence could be cut and pasted onto reports about deep avalanches on Saddle Peak, Buck Ridge, Cedar Mtn, Taylor Fork, Lionhead and Cooke City. The full list of <strong><a href="https://www.mtavalanche.com/avalanche-activity">Avalanche Activity</a></strong> is impressive.</p>

<p>For today, the avalanche danger is rated MODERATE because avalanches, especially large ones, are still possible.</p>

<p>If you get out, please send us your observations no matter how brief. You can fill out an&nbsp;<u><strong><a href="https://www.mtavalanche.com/node/add/snow_observation">observation form</a></strong></u>, email us (<u><strong><a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a></strong></u&gt;), leave a VM at 406-587-6984, or Instagram (#gnfacobs).</p>

<p>Last night’s 2-6” snowfall weighs only .2-.3”of <strong><a href="https://www.nrcs.usda.gov/wps/portal/nrcs/detail/or/snow/?cid=nrcs142p2… water equivalent</a></strong>, not a large load, but areas with fresh wind drifts may crack and/or avalanche in the new snow.</p>

<p>The mountain ranges are similar in terms of avalanche concerns and danger. Some areas might be a little stronger (Hyalite) and some a little weaker (Buck Ridge), but overall, sugary facets at the ground are occasionally avalanching the entire season's snowpack. In the last 7 days people triggered deep avalanches on this layer. As time goes on without a large storm the likelihood of triggering big slides decreases. Consider this analogy: After a large storm the backcountry might have 50, very hungry, Great White sharks swimming around ready to kill you.&nbsp; As days pass their numbers thin, leaving 2 or 3 on the hunt, like today. Yes, conditions are safer, but those sharks are still prowling and worth considering before you dip a toe into avalanche terrain.</p>

<p>Yesterday Ian rode towards Cedar Mtn. in the N. Madison Range to look at one of these shark attacks, an 8-10’ deep avalanche that broke at the ground after being triggered by a sledder on Sunday. Ian warns in his <strong><a href="https://youtu.be/XQQ8I9DJd98">video</a></strong&gt;, “As likelihood of triggering goes down, the consequences do not.”</p>

<p>Slopes with thick wind drifts can be triggered from shallow areas of the snowpack where the weak layer can collapse from the weight of a skier or snowmobiler. On Saturday I investigated a slide from last Tuesday in Cooke City that measured 15’ tall (<strong><a href="https://www.mtavalanche.com/images/20/15-crown-henderson-mtn">photo</a>…;, <strong><a href="https://youtu.be/VXVEIqSWvdY">video</a></strong&gt;), the deepest I’ve ever seen in 25 years of avalanche work that was likely triggered from a thin and rocky part of the slope (explained in this <strong><a href="https://youtu.be/MsjmwmAH7Ww">video</a></strong&gt;).</p>

<p>Before you head out today, do a little homework and read about these human triggered avalanches in <strong><a href="https://www.mtavalanche.com/node/21650">Hyalite</a></strong&gt; (Sat), <strong><a href="https://www.mtavalanche.com/node/21672">near Bridger Bowl</a> </strong>(Sun), on <strong><a href="https://www.mtavalanche.com/node/21707">Buck Ridge</a> </strong>(Sun, Mon), <strong><a href="https://www.mtavalanche.com/node/21652">Taylor Fork</a></strong> (Sat) and <strong><a href="https://www.mtavalanche.com/node/21706">Lionhead</a></strong&gt; (Mon). Our <strong><a href="https://www.mtavalanche.com/avalanche-activity">Avalanche Activity</a></strong> page has a complete list with details, pictures and videos. For today, since avalanches are possible the danger is rated MODERATE. Because the consequences of a slide are severe, it is also called a serious-moderate, scary-moderate, spicy-moderate, moderate-plus, or I-don’t-care-if-it’s-moderate-I’m-still-not-going-there-moderate. Check out Alex and Dave’s <strong><a href="https://youtu.be/TBygi0dYfQY">Dashboard Talk</a></strong> on this topic.</p>

<p>If you get out, please send us your observations no matter how brief. You can fill out an&nbsp;<u><strong><a href="https://www.mtavalanche.com/node/add/snow_observation">observation form</a></strong></u>, email us (<u><strong><a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a></strong></u&gt;), leave a VM at 406-587-6984, or Instagram (#gnfacobs).</p>