Snoqualmie Pass

The upper snowpack remains strong with melt-freeze surface conditions on some aspects. As crusts break down and the snow warms, don't let shallow loose wet avalanches catch you off guard in high consequence terrain. Create a buffer for the unlikely event a large open glide crack or cornice fails on the slopes above you.

A small storm over the weekend brought 2-4” of snow which moderate W winds redistributed Sunday night. Dry weather followed Monday and Tuesday, allowing the recent snow time to settle. 

Temperatures rose above freezing at all Alpental weather stations on Tuesday. NWAC forecasters and public observations from around the Pass reported extensive rollerballs and small, very shallow loose wet activity on steep, sun-exposed slopes. This activity posed a minimal hazard. By Wednesday morning you will find a crust that may or may not be supportable on W-S-E aspects. Milder temperatures and filtered morning sunshine will help to break down these crusts. Subsequently, we expect to add to the piles of rollerballs and shallow loose wet activity from Tuesday. These avalanches should not pose much danger except in high consequence terrain. If you choose to travel in rocky areas or above cliffs, keep the changing snow conditions on your mind. We expect loose wet activity to increase the avalanche danger on Thursday as rain may fall on previously dry northerly aspects at lower elevations.

Despite the spring-like weather, only the top few inches of snow on some aspects have made a spring transition. Below the surface, the snowpack remains dry, layered, and “winter-like.” You can still easily identify many of the recent storms, crusts, and interfaces. With mild temperatures in the forecast for the next few days cornices may fail, snow could shed from rock faces, and open glide cracks could avalanche. Although the timing of these avalanches remains elusive, you can mitigate these hazards with careful route planning and an eye to the slopes above you. 

At upper elevations, you will find textured snow and shallow wind drifts near ridgelines. You are most likely to find and trigger one of these thin slabs just in the lee of ridgelines or near the entrance to a confined chute. Watch for wind-ripples and textured snow surfaces to help anticipate nearby slabs. Use caution if you decide to continue into these potentially wind-loaded features.

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.