18-19

<p>On Saturday I placed a fellow skier in a body bag after an avalanche pushed him through trees. The accident provided clarity to something that can seem vexing: on a steep slope, when are trees a sign of safety? The answer is that for skiers (or snow bikers), most of the time they are not. If trees are spaced far enough apart that a skier could link more than a couple turns, then the slope is open enough to avalanche. Instead of tree density, pay attention to slope angle. This accident, plus the avalanche south of Livingston on Saturday (<strong><a href="https://www.mtavalanche.com/node/19877">details</a></strong&gt;) and another on Mt. Ellis on Sunday (<strong><a href="https://www.mtavalanche.com/node/19903">details</a></strong&gt;), all involved avalanches in fairly dense timber. When the snowpack is unstable or tricky to assess, our only safe bet is to avoid avalanche terrain (measured as anything over 30 degrees steep). And the best way to do that is to rely on slope angle instead of seeking safety in trees.</p>

<p>Over the weekend there was a mob of avalanche activity. Some people were caught in slides (the <strong><a href="https://www.mtavalanche.com/node/19852">Throne</a></strong&gt;), some people triggered them (<strong><a href="https://www.mtavalanche.com/node/19873">Bradley Meadow</a></strong>, <strong><a href="https://www.mtavalanche.com/node/19876">Cedar Mtn</a></strong>) and others just saw the aftermath. Our forecast area is large, so take a few minutes to check out our <strong><a href="https://www.mtavalanche.com/avalanche-activity">Avalanche Activity List</a></strong> to see if there’s been any action in the area you’re headed to today. Recent avalanche activity, collapsing or cracking, indicate dangerous conditions and should override any positive feelings you might have about a slope’s stability.</p>

<p>We have weak snow near the ground and we had a lot of snowfall late last week. With time, stability is improving and it is getting more difficult to trigger avalanches, but there are spots where it is possible. These areas will either be wind-loaded or shallow and unsupportable. Ian was in Taylor Fork on Sunday and was able to trigger a slide in one of these spots from 50’ away (<strong><a href="https://www.youtube.com/watch?v=hh3eSrv6fYI">video</a></strong&gt;, <strong><a href="https://www.mtavalanche.com/images/19/sunlight-basin-avalanche-2">photo…;). Sinking to your waist in sugary snow is a serious concern because it means the underlying snowpack is weak and potentially unstable. Although triggering slides is getting harder, it’s definitely possible, especially on slopes with recent wind-drifted snow. For today, the danger is rated MODERATE throughout our advisory area.</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>

<p>Don’t let today’s blue skies lull you into complacency, weak layers are still reeling from the heavy load that accumulated over two weeks of steady snowfall. Large avalanches remain easy to trigger.</p>

<p>Yesterday, large natural avalanches were seen on Fan Mountain, near Big Sky (<strong><a href="https://www.mtavalanche.com/node/19920">details</a></strong&gt;), Sheep Mountain, near Cooke City (<strong><a href="https://www.mtavalanche.com/node/19924">details</a></strong&gt;), and on Mount Blackmore, in Hyalite (<strong><a href="https://www.mtavalanche.com/images/19/natural-avalanche-blackmore">phot…;). The slide on Sheep Mountain broke up to 8’ deep in a thick wind drift. Big Sky ski patrol also triggered a large avalanche yesterday that broke 3-5’ deep on weak layers near the ground (<strong><a href="https://www.mtavalanche.com/node/19922">details</a></strong&gt;). Yesterday’s avalanches are just the latest in the string of natural and human triggered avalanches that have been reported every day for almost two weeks (<strong><a href="https://www.mtavalanche.com/avalanche-activity">avalanche activity</a></strong>), including multiple skier triggered avalanches this weekend (<strong><a href="https://www.mtavalanche.com/node/19852">details</a></strong&gt;, <strong><a href="https://www.mtavalanche.com/node/19873">details</a></strong&gt;, <strong><a href="https://www.mtavalanche.com/node/19903">photos and details</a></strong>), and a skier killed in an avalanche in the Tobacco Roots on Friday (<strong><a href="https://www.youtube.com/watch?v=B6T7SQNvwsQ&amp;list=PLXu5151nmAvRNl9ku…;

<p>Give steep terrain a wide berth, as you could trigger an avalanche from a distance, either from below, or from connected lower angle terrain. On Sunday, my partner and I triggered an avalanche from 50’ away on flat ridgeline in Taylor Fork (<strong><a href="https://www.youtube.com/watch?v=hh3eSrv6fYI&amp;index=2&amp;t=0s&amp;li…;, <strong><a href="https://www.mtavalanche.com/images/19/sunlight-basin-avalanche-2">photo…;). There have also been multiple reports of slides on lower angle avalanche terrain, just over 30 degrees steep (<strong><a href="https://www.mtavalanche.com/node/19857">details</a></strong&gt;).</p>

<p>Patience and restraint are the name of the game today. Without more snow in the short term forecast, avalanche conditions will slowly improve. There will be a time for riding steep slopes, it just isn’t here quite yet.</p>

<p>Today, triggering a large and dangerous avalanche is likely. Avalanche danger is <strong>CONSIDERABLE</strong>.</p>

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