Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
1 · Low
Treeline
1 · Low
Below
1 · Low
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Out of date — this forecast expired 6 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

If you decide to take advantage of the nicer weather Saturday by heading into the mountains, be prepared to make your own hazard assessment. If you find that the snow is deeper than you expected or you see it being blown around, realize that avalanche danger could be increasing and be prepared to change your travel plans. Remember that even a small avalanche could have large consequences in big terrain.

Avalanche problems

  • Loose Dry

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    1

    Recent snow fell on a stout rain crust and with the right conditions, could produce Loose Dry avalanches on Saturday. Often called sluffs, Loose Dry avalanches start at a point, then entrain additional snow and fan out as they move downhill. These slides have the ability to run quickly and knock you off your feet, so be aware of where you are in terrain and avoid stopping underneath steep slopes or near terrain traps. Unsupported slopes, large terrain features steeper than 35 degrees, and any slopes with evidence of wind-drifted snow have a higher likelihood of producing these avalanches.

    (3/8/2020) Example Dry Loose: This dry loose was triggered by a skier at an initial point, then entrained snow and fanned out as it moved downhill. Don't get caught by one of these in consequential terrain.

Avalanche Discussion

Multiple rounds of precipitation impacted Snoqualmie Pass earlier this week, leaving in their wake a new crust (12/9) overlaid by up to 8” of snow at middle and upper elevations. You should find generally safe avalanche conditions throughout the zone, but that doesn’t mean that danger does not exist. Take note of how the weather changes throughout the day and any corresponding changes with the snow. If the sun is out for a prolonged period of time Saturday, it could destabilize the new snow on slopes that receive direct sunlight and produce a few rollerballs and pinwheels as precursors to Wet Loose avalanches. As for areas that are holding colder and drier snow, watch out for Dry Loose avalanches and the possibility of small wind slabs forming throughout the day as winds increase. Although unlikely, any avalanches should be small in size and confined to the upper snowpack above the 12/9 crust. When in doubt, you should default to low-angle terrain.

Recent weather wreaked havoc on the snow around Snoqualmie leaving us with variable and potentially difficult travel conditions. Firm surfaces abound under the recent fresh snow. Be confident in your ability to arrest in case of a fall. The snowpack at lower elevations eroded during the warm and wet weather amplifying early season conditions. You will likely encounter numerous open creeks, downed logs, and exposed obstacles. Give yourself extra time to deal with these demanding conditions.

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.

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