Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

New snow arrived in the nick of time for the holiday weekend.  As you enter mid and upper elevations you'll likely encounter freshly formed wind slabs below ridgelines.  Know the consequences of the terrain - the chance of injury in a small avalanche are real due to a rough early season snowpack.  You'll find improved but still challenging travel at lower elevations.  

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Strong winds have been consistently out of the W-NW since the storm began on Friday and they will continue drifting new snow through Saturday morning.  Storm conditions are forecast to taper off quickly late Friday night and Saturday morning. 

    As you ascend in elevation and enter more exposed terrain look for evidence of wind-stiffened and textured snow as well as shooting cracks.  These signs will help you steer around steep open slopes with obvious signs of recent wind-loading.  You can expect to find thicker and more consequential wind slabs closer to ridgelines. Choose your terrain carefully - don't let a small avalanche knock you off your feet and take you for a rough ride in these early season conditions.

    If the sun comes out for an extended period on Saturday, you may see small loose avalanches release naturally from steep rocky terrain features.  

    (2/18/2023)

    Example: Signs of wind loading to look for Saturday. 

    Photo: Dallas Glass

Avalanche Discussion

Ahhh, fresh snow in December feels like a cause for celebration especially given how this season has started.  Around 8" of new snow piled up quickly Friday afternoon in the Snoqualmie area along with consistently strong ridgeline winds out of the W-NW.   Several more inches are likely Friday night. Since this forecast is banking on a Convergence Zone behaving overnight, that means we'll have to see how much more new snow arrives in the narrow but intense bands that define this local weather pattern. 

This storm started warm with some light rain reported at Pass level including at similar elevations where surface hoar was reported on the 21st.  Most likely the right-side up (warm to cold) nature of the snowfall and the rough and variable pre-storm snow surfaces should promote good bonding on the new snow to old surfaces.  That said, early season conditions have left us without the usual number of observations for this time of year.  Use quick hand pits and test slopes to gather information on the layering and stability of the upper snowpack.  

While the new snow is more than welcome it will take more than one storm to significantly improve the low snow travel hazards. Creeks, rocks, logs, holes, shrubs, and trees all still exist and can make even easy travel routes quite treacherous. Take it slow and give yourself time to deal with the persistent early season conditions.  

We know some of you will be out taking advantage of the conditions - please take a few minutes and share what you're seeing through an observation. 

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