Snoqualmie Pass

You should find generally safe avalanche conditions around the Pass Saturday. That doesn’t mean you can’t encounter an isolated pocket of unstable snow in wind-affected alpine terrain or on steep rocky slopes during sitting in the sun.

Saturday will be a bit of a transition day ahead of a much more active weather pattern. As a result, you’re likely to find generally stable snow and possibly challenging travel conditions. Expect breakable crusts, icy slopes, hard rough surfaces, frozen avalanche debris, open creeks, and lingering pockets of powder as you travel. 

After several days of quiet weather, most avalanche issues should have settled out and gained strength. If you’re going to run into unstable snow, there are two possibilities. 

- Wind Affected Alpine Terrain: Several observations on Wednesday found thin hard wind slabs overlaying facets in large open alpine terrain. Now, these wind-loaded pockets are several days old and should be very hard to trigger. Nonetheless, keep them on your radar if your plans take you onto the shaded side of some of the Pass’s larger peaks. Look for firm (but not icy) and smooth pillow-like drifts to avoid these potential small avalanches. 

-Loose Wet: With warming temperatures and the possibility for some sunshine, you could see the shallow soft surface snow become wet and weak. This will likely only result in piles of rollerballs. However, you could see a few small loose wet avalanches. These natural slides would most likely originate from steep rocky slopes during periods of sunshine. 

As we head into a more active weather pattern, we’ve got our eye on some weak sugary facets in the upper snowpack. You can help us find where these potential weak grains exist and are absent by submitting an observation from your travels on Saturday. So far, we consistently found the 3/8 facets just above the very prominent Early March Crust (formed by the atmospheric river) on NW-N-NE aspects above 4500 ft. These angular grains are small (1-1.5mm) and bounce around on your shovel or in your hand. They have been noticeably absent at lower elevations and on sunny slopes. 

By late Saturday afternoon, you may find weather conditions deteriorating rapidly. The first in a series of storms should arrive in the evening hours.