Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

The mountains are in for a big change as rain reaches well above ridgetops. Wet avalanches of every type and size could occur, including natural slides. If you experience sustained heavy rain or see bigger avalanches, the scales may be tipping towards a very dangerous situation.

Avalanche problems

  • Wet Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2.5

    You’ll certainly see wet loose avalanches, but as water percolates deeper into the snowpack, conditions could get much scarier. Wet slabs, glides, cornice collapses, and wet loose slides gouging into older snow layers could all occur. The tricky part is the timing. This atmospheric river isn’t particularly potent. Picking if and when the snowpack will reach the breaking point is nearly impossible. 

    The uncertainty around wet avalanches is very real and should cause a much higher level of caution. You could trigger a slide on any steep open slope. Because natural avalanches may occur, consider limiting any time you spend where slides run and stop. 

    Most of the natural activity will be relatively small, but a few isolated larger avalanches could release. Things could become much more dangerous than anticipated if you see heavy rainfall or notice avalanches gouging into older snow layers. If you suspect this is the case, get out of avalanche terrain.

    Example: (1/15/2023) A very large wet slab avalanche on the W Face of Kendall. W, 5600ft, WS-N-D2.5-R2-U, likely from the 1/12-13 cycle. Photo: Dallas Glass

Avalanche Discussion

The old adage, “Big changes mean big problems,” has been ringing in my head all day. This is certainly a big change for the snowpack as we move from mild and wet to hot and soaked. We anticipate dangerous conditions on Saturday, but there’s a chance things could be worse than expected with higher avalanche danger. 

The real concern is that despite the relatively warm temperatures of the past week, only the upper few inches of snow transitioned to the added heat. Below the surface, the snowpack remains very cold, dry, and layered. This includes several older crust layers and lingering facets. These go all the way back to the Solstice Matrix 4-6ft below the surface. If some of these deeper layers wake up… look out! 

On Friday, avalanche professionals reported breakable crusts, wet sticky snow, rollerballs, and a few very small wet loose avalanches. The crust was often weak and breakable below about 4800ft. Runnels in the snow surface showed the upper snowpack became wet during the recent mild weather. Below the crusty wet surface, the snowpack still remained cold, dry, and layered particularly at middle and upper elevations.

Regions covered