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GNFAC Avalanche Forecast for Tue Nov 28, 2017

Snowpack and Avalanche Discussion

<p>The weather this last week has given us a good whiplashing: snow, then rain, then shorts and sunscreen, then more rain, then snow yesterday morning. This has played havoc on the skiing and riding conditions, but as an avalanche forecaster I’m smiling because this wacky weather helped create a generally stable snowpack. There’s a lack of widespread weak layers and the temperature swings and rain helped densify and strengthen the snow. The mountains have 2-3’ of dense snow with close to 6’ outside Cooke City. Yesterday, Eric found soggy snow below 9,000’ in the Bridger Range and skiers reported similar mushiness at low elevations in Beehive Basin and Cook City. This will freeze in the next few days and strengthen the snowpack even further.</p>

<p>Yesterday’s new snow was blown by westerly winds (<strong><a href="https://www.mtavalanche.com/images/17/mt-blackmore-wind-loads">photo</a…;) forming wind slabs near the ridgelines. Skiers on Mt. Blackmore got a few drifts to crack while the Big Sky Ski Patrol reported wind-loaded slopes stubborn to avalanche. This new snow fell onto a variety of surfaces ranging from an ice crust to moist snow. In most instances it bonded to the old surface, but dig 1-2’ deep to this interface to confirm the stability before exposing yourself to avalanche terrain.</p>

<p>Moist snow at lower elevations and wind-loading up high point to the possibility of human triggered slides. For today, the avalanche danger is <strong>MODERATE</strong>.</p>

<p>Our forecasting season has just begun and we are being conservative with our assessments as we gather more snowpack information. I am pretty happy that the snowpack does not have widespread weak layers, but there are a few slopes that could surprise us. A <strong><a href="https://www.mtavalanche.com/images/17/pebble-creek-26-nov">snowpit</a><…; showing instability and a small wet slab (<strong><a href="https://www.mtavalanche.com/images/17/natural-avalanche-cooke-city-0">p…;) outside Cooke City last week are both reminders to not let our guard down.</p>

<p>If you get out and have any avalanche or snowpack observations to share, drop a line 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>

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