Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Thu
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Wet avalanches will continue to be a concern on Wednesday as rain returns to Snoqualmie Pass. These unpredictable slides could occur without warning on steep slopes that didn’t shed over the weekend. The poor weather and travel conditions may be an excellent excuse to sit this storm out and wait for better stability in a few days.

Avalanche problems

  • Glide Cracks

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–3

    Despite the rain and warm temperatures, not every slope or rocky ledge has shed over the past week. At least one glide avalanche occurred on Tuesday. Additional rain may keep avalanche activity going on Wednesday. Keep an eye out for sagging cornices, glide cracks, or precariously perched blocks of snow to help identify areas where shedding avalanches could occur. They could fail without warning, possibly triggering slabs or loose avalanches on the slopes below. Give these areas a wide berth as you travel.

    (1/30/2024)

    A glide avalanche on Rockface at Alpental. This frequent flier is a good indicator that water is still making its way through the snowpack. We're not done with wet avalanches.

    [E 3900' WS-N-R2-D2-G]

    Photo: Alpental Pro Patrol

Avalanche Discussion

Liquid water from this past weekend’s atmospheric river is still moving through the snowpack, resulting in avalanche activity. On Tuesday, Alpental Pro Patrol reported that a glide avalanche occurred on Rockface - a frequent producer. They also reported other shedding-type avalanches near the base of cliffs. The slow trickle of wet avalanche activity is due to the influx of rain combined with unseasonably warm temperatures that haven’t dipped below freezing since Friday afternoon. 

We expect that slow trickle to continue through Wednesday due to another round of rain. This isn’t a favorable flow pattern for our zone, and the snowpack should be reasonably well-suited to accept additional liquid water. That said, it should be an uptick more dangerous than it was on Tuesday.  

Additionally, if we overproduce on our water numbers, rain could soak deeper into the snowpack where the snow is drier, and our old layers of concern may still be lurking. In neighboring zones, very large and destructive avalanches have recently been commonplace, many involving these same layers. If they start to get wet and produce more widespread wet slab activity, you should avoid all avalanche terrain.

Over the weekend, we had a significant wet avalanche cycle as an atmospheric river impacted the zone. NWAC forecasters documented slides up to size D3 on Monday morning. Although we expect the height of natural avalanche activity to have passed, this period of unpredictable wet avalanches won’t truly be over until temperatures drop and the surface starts to freeze. 

Heavy wet snow, runneled surfaces, running water, and avalanche debris now litter the landscape, possibly making for challenging travel conditions. 

Regions covered