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
2 · Moderato
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Non aggiornato — questo bollettino è scaduto 3 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Wet avalanche issues will continue to be a concern until temperatures cool significantly and the snowpack freezes. Pay attention to the terrain above you. Choose routes that help limit the time you spend under steep rocky slopes, especially where you see crevasse-like cracks or overhanging waves of snow.

Problemi valanghivi

  • Loose Wet

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

    If you find wet punchy snow, you may trigger loose wet slides in nearby steep terrain. You will most likely encounter these conditions during the warm, sunny weather expected Tuesday afternoon. So, keep your eye on the snow surface, if you experience wet sticky snow, see new rollerballs, or find fresh fan-shaped debris expect loose wet slides on similar aspects. 

    While you may trigger these avalanches on steep slopes, they could also occur naturally. Fortunately, their relatively small size should limit their impact; just don’t let them push you into a creek or over a cliff.

    (3/18/2023)

    Multiple Wet Loose avalanches occurred during sunny weather on 3/18. Most of these originated near rocky terrain.

    Photo: Public Observation

  • Glide Cracks

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    2–3

    The recent warm weather has us concerned about the snowpack falling down. This could be a glide avalanche, a failing cornice, or a smaller slide stepping down to older snow layers. In all cases, these larger destructive avalanches are very hard to predict. The best way to avoid this issue is by paying attention to the terrain above you and minimizing any time you spend under large complex terrain. Three situations to pay particular attention to where these very large avalanches may be more likely:

    1: Slopes with glide cracks

    2: Ridgelines with large overhanging cornice

    3: Complex rocky terrain receiving direct sunshine.

    (3/18/2023)

    This glide crack was spotted on 3/18 and is an example of overhead hazard on a slope that could release during the warm spell. [W 4500']

    Photo: Public Observation

Avalanche Discussion

It’s hard to call conditions “generall safe” (Low danger) when temperatures are this warm. In fact, Tuesday could be the third day in a row without a solid overnight freeze at the Pass. While you may not see a single very large natural avalanche, most of the pieces are in place for them to occur. This is the first major spring transition our cold dry and wintery snowpack has experienced. Predicting exactly how the snow will respond to this big change is quite challenging and brings with it a lot of uncertainty. 

A little bit of precipitation and slightly cooler temperatures Monday night into Tuesday morning may not drive additional avalanche danger, but they won’t do much to promote stability either. As the sun comes out Tuesday, that could cause conditions to worsen and result in the greatest hazard in the afternoon. 

Numerous natural loose wet avalanches were reported around the zone Saturday and Sunday. Most occurred during the peak of the warm, sunny weather on 3/18. While the snow surface on sunny aspects and at lower elevations has been influenced by the recent weather, you may still find cold dry snow on more shaded areas higher in the terrain.

Regioni coperte