East Slopes South

While the avalanche danger is decreasing, recent winds and snow at upper elevations formed slabs that you can trigger. Steer around lee slopes steeper than 35 degrees and where you see signs of recent wind transport, firm or textured snow, or cracks forming in the snow as you travel. If the sun comes out, use roller-balls as a sign that loose wet avalanches could entrain the recent snow to produce small, but potentially harmful loose wet avalanches.

Our snowpack is far above average for this time of year with mid-elevation snowpacks in the 20-30" range, with over 40" just to the west of this zone at White Pass. After our initial snowfall, a rain event and warm period built a supportable rain crust on November 16th. This has served to lock in the base of the snowpack and batter down vegetation creating surprisingly good travel conditions and snow coverage for November.  Snow that fell last week is generally well bonded to the 11/16 rain crust and no significant avalanche activity was observed in the recent snow.  Friday and Saturday (11/20-21) brought sunny, calm, and warm conditions. The snow surface stabilized as a crust formed on solar aspects and lower elevations. Higher elevation and shaded slopes largely escaped the melt cycle and good travel conditions were found on these slopes throughout the weekend. Winds on Tuesday were able to redistribute the small amount of new snow from Monday and develop wind slabs at upper elevations on lee slopes and with temperatures warming up, a crust may have formed in some locations. 

A storm arriving Tuesday night brought 2-6" of snow and wind to the mountains. Expect to find wind slabs on near and above treeline on lee slopes. Larger wind slabs will be more likely at higher elevations where wind has been persistent since Monday.  Look for signs of recent wind transport such as blowing snow and cornice development to clue you into where slabs might have formed. Stay alert for firm and textured snow surfaces and cracking in the snow as you travel as evidence that you could trigger a wind slab.  When in doubt, choose lower angle terrain (less than 35 degrees) and navigate away from features such as cornices and convex rolls.  

The weather will be quieter on Turkey Day with generally light winds and increasing chances of sunshine as the day wears on. This should allow wind slabs time to begin to heal. However, if the sun comes out, expect small loose wet avalanches to develop in unconsolidated snow on sun-exposed slopes steeper than 35 degrees. The sun may be just strong enough in late November, so keep your eye out for roller ball activity or wet snow surfaces as a precursor for a loose wet avalanche and adjust your aspect to shaded terrain.

Despite the great start to our winter snowpack, keep early season conditions in mind. Rocks, stumps, and vegetation may be barely covered and many creeks are open.

The Covid19 pandemic continues to be a major health and safety concern. Avoid unnecessary risks that could result in a rescue or stress medical resources. Follow local and state guidelines and wear a mask when appropriate. Maintain social distance and recreate responsibly and closer to home.

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