Bollettino valanghe

Snoqualmie Pass

Northwest Avalanche Center
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Pericolo valanghe

Wed
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
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In sintesi

You may encounter pockets of wind-drifted snow as you start to gain elevation and approach some of the rockier peaks and ridgelines. Steer around pillow-like slabs you find near the tops of chutes, along the base of cliffs, or below sharp cornices.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    Recent winds managed to drift the few inches of new snow into small slabs at mid and upper elevations. While these wind-loaded pockets won’t be everywhere, they should be on your mind as you start to move higher in the terrain. Unfortunately, they could hide under a dusting of new snow, so you’ll need to look carefully. If you see pillow-like slabs or slopes that look “fat” with more snow than surrounding areas, you’ve found the problem. You’re most likely to see this near the tops of chutes, along the base of cliffs, or under sharp cornices. Indeed a small wind slab avalanche was observed on Monday below Bryant Peak that fit just this description. While we think most of these slabs should remain small and relatively harmless, they could still hurt you if they flush you down a couloir or carry you over a cliff.

    (1/16/2023)

    A wind slab avalanche along the base of cliffs on Bryant Peak in the Alpental Valley. E, 4800ft, SS-U-D1.5-R2U

    Photo: Jeff Tarshis

Avalanche Discussion

Cooling temperatures and a return to snow at Pass level are helping things feel a bit more winter-like again around the zone. As of Monday afternoon, snow totals over the 1/14 crust range from 2in (5cm) at lower elevations to 6+in (15cm) at mid and upper elevations. You may find another inch or so on Tuesday morning, but this weather pattern doesn’t appear to bring any significant precipitation or wind to the area until Wednesday. 

A surprise bit of sunshine on MLK day caused the new snow on steep southerly slopes to become wet and unstable. It resulted in a few natural rollerballs and small loose wet avalanches. Most of these slides traveled on the newly formed 1/14 crust. If the sun comes out again Tuesday you could see similar small wet slides. 

The most meaningful observation from Monday was a small wind slab avalanche on the E face of Bryant Peak. Slides like this demonstrate the ability of wind-sifted snow falling down cliff faces to build slabs along the base of rocks. 

Below the new snow, the 1/14 crust continues to grow thicker and stronger. This will most likely result in variable travel conditions with punchy snow, breakable crust, frozen avalanche debris, firm surfaces, and pockets of deeper powder. Last week’s rain event left the mountains littered with piles of frozen avalanche debris. While we anticipate the wet hazards from this storm have ended, don’t linger under steep rocky slopes holding onto blobs of heavy wet-looking snow.

Regioni coperte