Stevens Pass

Expect warm temperatures and sun for Thursday. While conditions are generally safe, consider the consequences of a large cornice fall. You may find isolated areas where snow could slide on very steep, unsupported slopes either above treeline or on sunny, south-facing slopes.

While avalanches are unlikely on Thursday, there are still considerations to keep in your mind. Don't linger on or under cornices. If you're traveling on a ridge, and give them a wide margin. Observations from last week, and more recently in other zones are evidence that cornices have been falling. It's worth keeping wet avalanches on your mind, especially on sunny slopes over 40 degrees and around terrain traps. Finally, you may find shallow, older wind slabs at upper elevations. These will be difficult to trigger. On Sunday and Monday, observers reported a couple of small, natural avalanches along with wind transport near and above treeline. 

Deep persistent slab avalanches hold the potential for huge consequences. While these massive avalanches are dormant and unlikely, the snowpack structure can still be found. The mid-January crust-facet layer is now 8-9 feet below the surface and showing signs of strengthening. The last known deep slab avalanche in this zone was on March 1 with another suspected in the West South zone on March 3. Major warming events later in spring and summer could trigger further rounds of avalanches on this layer. Keep in mind the consequences of these massive avalanches and give yourself an extra margin of terrain large avalanche paths.

On March 1st, WSDOT avalanche teams triggered an 8ft deep D3 avalanche on the southeast face of Rock Mountain east of Stevens Pass. In the Chiwaukum Mountains, a natural D3.5 avalanche in upper-elevation north-facing terrain is suspected to have run on the 28th. A massive avalanche (D4) ran naturally in the West Camp path on Rock Mountain less than 2 weeks ago. These are just a few of the very large and historic avalanches that occurred in the second half of February.

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources.  Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.