Bollettino valanghe

Olympics

Northwest Avalanche Center
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Pericolo valanghe

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

Strong sun and rising freezing levels will maintain the danger of wet avalanches, especially on southerly aspects. Steer around steep slopes with unsupportable wet snow surfaces. Identify and avoid traveling under cornices and other unstable, melting snow features in steep and rocky terrain above you.

Problemi valanghivi

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    The primary danger on Friday will be from unconsolidated loose wet snow avalanches in steep terrain. Though you could trigger or be overrun by these avalanches on any aspect, the highest likelihood is in terrain where the sun is melting and further weakening the snow surface. You could trigger loose wet avalanches on steep slopes where you are skinking past your ankles in wet snow. 

    In addition, avoid traveling under sagging cornices, glide cracks that indicate the entire snowpack is slipping on the ground below, and other steep, rocky, snow covered terrain. Though the likelihood is low any of these hazards will release naturally in terrain above you, the consequences would be devastating. These are not dangers that can be “managed” in the terrain - all you can do to reduce risk is to stay away from steep terrain features that could produce large, wet avalanches.

     

    (1/11/2022)

    Example of a recent loose wet avalanche triggered by rainfall.

    Photo: Lee Lazzara

Avalanche Discussion

Hurricane Ridge picked up 1.5” of precipitation since January 10th falling nearly all as rain. Observers in the same area today noted a general lack of avalanches from the last few days with observed activity limited to small glide avalanches on road cuts and shedding cornice chunks. A supportable crust was noted on solar aspects while shaded aspects were less supportable. Below the surface crust, the snowpack consisted of alternating melt form and rounded grain layers down to the Solstice Crust. No significant snowpack test results were reported. Snow depth ranges from 100-170cm varying by aspect and exposure to wind.

Last weekend NPS rangers and observers noted that S-SW aspects along ridgelines were largely stripped of snow and had a semi-breakable crust.  On northerly aspects and away from wind effect, the storm snow was largely right side up.  Natural cornice fall triggered at least two large wind slab avalanches between Friday afternoon and Saturday afternoon in the Hurricane Ridge area.   On Sunday, ONP Rangers noted several natural loose wet avalanches on steep sunny slopes. 

2021-22 Forecast Schedule: Avalanche danger ratings will be issued for the Olympics every Friday through Sunday and during mid-week holidays. During the week when the Hurricane Ridge road is closed, forecast information will be updated daily to include expected conditions and relevant travel advice under the No Rating label.

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