17-18

GNFAC Avalanche Forecast for Sat Oct 21, 2017

Snowpack and Avalanche Discussion

<p>Wind and new snow make it possible to trigger avalanches this weekend. Westerly wind will drift snow into thick slabs that could be triggered by skiers, hunters, or ice climbers. These fresh wind slabs should be completely avoided in steep terrain. Terrain traps such as rocks trees and gullies increase the consequences of even the smallest slide, and are more prevalent right now due to thin snow cover. Avalanches can pile debris deep in gullies and confined terrain, and slides are deadly above cliffs like on the approach to climbs on the Sphinx.</p>

<p><u>Ice climbers</u> should completely avoid steep, high consequence terrain if it’s loaded with fresh snow, and turn around at the first sign of instability such as cracking of fresh drifts. A small, 15’ wide avalanche killed two climbers on the Sphinx in October 2004.</p>

<p><u>Hunters</u> often travel solo and don’t carry avalanche rescue gear, so should completely avoid steep, snow covered avalanche terrain. Avoid deep, dense or hard drifts of snow near ridgelines and on the steep sides of gullies. If necessary, cross these features one at a time, at the top versus mid-slope, and watch each other from a safe area.</p>

<p><u>Skiers</u> need to carry rescue gear as they normally would in the middle of winter (Beacon, Shovel, and Probe). Put fresh batteries in your beacon and practice using it, check your probe and shovel for damage, and check your partners’ gear before you leave the trailhead. Slopes with the most snow are the most attractive to ride as they are smooth and rock free, but are also more likely to have fresh drifts that could avalanche. Assess the snowpack and avoid steep terrain if you see collapsing or cracking of the snow.</p>

<p>Before this weekend’s snow there was 1-3 feet of snow on shady, high elevation slopes while sunny and wind scoured slopes had little to no snow (<strong><a href="https://www.mtavalanche.com/images/17/cooke-city-snowpack-oct-15">photo…;, <strong><a href="https://www.mtavalanche.com/images/17/lionhead-ridge-19-oct">photo</a><…;, <strong><a href="https://www.mtavalanche.com/images/17/lionhead-weather-station-19-oct">…;, <strong><a href="https://www.mtavalanche.com/images/17/snowpit-near-imp-peak-avalanche">…;). Short days and less direct sunshine mean this snow is likely here to stay. These layers are the foundation of our snowpack. Now is the time to start observing their distribution, and their behavior during and between storms. If you get out and have any avalanche or snowpack observations to share, drop a line via our website, email (<a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a&gt;), phone (406-587-6984), or Instagram (#GNFACobs).</p>

<div>
<hr /></div>

<p>We will update daily weather information on our website after storms, and issue early season bulletins as conditions warrant.</p>

<div>
<hr /></div>

Powder Blast Fund-raiser

27 October, 6:30 p.m. at the Emerson Cultural Center. Tickets and Info

Lionhead weather station is up. The early season snow has stuck around most higher elevation, shady slopes, while sunnier slopes have little to no snow. The remaining snow will be the foundation for this winter's snowpack and a layer to keep an eye on. Photo: GNFAC

Lionhead Range, 2017-10-20

In the montains around Cooke City, 1-2 feet of dense snow exists above 9,000 ft. This will likley make up the foundation of the winter snowpack. Fortunately, this base layer has gained strength with recent warm weather and should be a strong foundation for future snows. Photo K. Broderick 

Cooke City, 2017-10-17

GNFAC Avalanche Forecast for Sat Oct 14, 2017

Snowpack and Avalanche Discussion

<p>New snow and winds are creating drifts which will be easy to trigger this weekend. Underneath this new snow is a snowpack measuring 1-3 feet thick with layers of dense slabs overlying looser, weaker (slightly faceted) snow. This was the snowpack we found in the southern Madison Range on Imp Peak (<strong>photo</strong>, <strong>snowpit</strong>). Avalanches can be triggered and even small ones can be deadly. The avalanche last week was not very large and released on a steep rollover that was drifted with hard slabs of wind-blown snow.</p>

<p><u>SKIERS</u>: Carry rescue gear as you normally would mid-winter (beacon shovel, probe) and turn your beacon on when you put your skis on, if not before. Be alert for cracking or collapsing of the snow which is a sign of instability. Stay off of wind-loaded terrain even though these slopes are attractive because they are deep, smooth and rock free, and only expose one person at a time to avalanche terrain.</p>

<p><u>ICE CLIMBERS</u>: My biggest concern are those headed to the Sphinx in the southern Madison Range. The avalanche on Imp Peak was only 11 miles away and the snowpack is likely similar in structure. A small, 15’ wide avalanche killed two climbers in October 2004. Assess the snow and turn around at the first sign of cracking on the traverse.</p>

<p><u>HUNTERS</u>: Hunters typically travel solo and carry no rescue gear. Their primary line of defense is to avoid avalanche terrain. If you have to cross gullies, do so at the top versus mid-slope and if possible, have someone watch you.</p>

<p>No matter if you are a skier, climber or hunter, the snow does not care. Carry rescue gear and know how to use it, travel one at a time in avalanche terrain and pay particular attention to open slopes, especially where the wind has deposited thick slabs of snow.</p>

<div>
<hr /></div>

<p><strong>AVALANCHE FATALITY</strong></p>

<p>On October 7, two skiers were caught, one was fully buried and killed, and one was partially buried in an avalanche on Imp Peak in the southern Madison Range.</p>

<p>Video of the accident investigation can be found <a href="https://youtu.be/OhTV6YMPOZc"><strong>here</strong></a>.</p&gt;

<p>Read the full avalanche accident report <a href="http://www.mtavalanche.com/accident/17/10/12"><strong>here</strong></a>…;

<div>
<hr /></div>

<p>This month we are preparing for winter, scheduling avalanche classes, and setting up weather stations. If you get outside send us an observation via our website, email (<a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a&gt;), phone (406-587-6984), or tag us with #gnfacobs on Instagram (@mtavalanche).</p>

Upcoming Events and Education

Powder Blast Fund-raiser

Friday, 27 October, 6:30 p.m. at the Emerson Cultural Center. Tickets and Info

GNFAC Avalanche Forecast for Thu Oct 12, 2017

Snowpack and Avalanche Discussion

<p>All the necessary ingredients for avalanches currently exist in the mountains. New snow combined with moderate to strong wind out of the W-SW will elevate the avalanche hazard over the next few days. Wind loaded slopes will be the most avalanche prone and should be approached with caution. Areas of wind deposited snow likely exist below upper elevation ridgelines or on the leeward side of cross-loaded terrain features (<a href="http://www.mtavalanche.com/images/17/wind-transport-lone-mountain-11-oc…;). This presents a quandary because wind-loaded slopes offer the best skiing, but are also the most likely to produce a slide.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</p>

<p>It’s important to remember that even small avalanches can injure or kill. It doesn’t matter if you’re a beginner or expert, a skier or hunter, avalanches don’t discriminate. With an existing avalanche danger present in the mountains, it’s necessary to follow the three simple rules of backcountry travel:</p>

<ul>
<li>Carry rescue gear (beacon, shovel and probe) and know how to use it.</li>
<li>Only expose one person at a time in avalanche terrain, both heading up and sliding down.</li>
<li>Always watch your partner from a safe location.</li>
</ul>

<p>With snow on the ground, now is a good time to sharpen our minds and check our gear. Replace batteries in your beacon, recharge your airbag, make sure probe poles and shovel parts fit together smoothly. There are many avalanche education opportunities this fall. Check out the full education offerings <a href="http://www.mtavalanche.com/education"><strong>HERE</strong></a>.</p&gt;

<div>
<hr /></div>

<p>This month we are preparing for winter, scheduling avalanche classes, and setting up weather stations. If you get outside send us an observation via our website, email (<a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a&gt;), phone (406-587-6984), or tag us on Instagram (#gnfacobs).</p>

Powder Blast Fund-raiser

Friday, 27 October, 6:30 p.m. at the Emerson Cultural Center. Tickets and Info