Bollettino valanghe

West Slopes Central

Northwest Avalanche Center
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Pericolo valanghe

Thu
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
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Non aggiornato — questo bollettino è scaduto 6 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Human triggered avalanches are possible as we continue to receive more snow.  Reports from nearby areas on Tuesday revealed reactive yet unpredictable avalanche conditions.  Stay off slopes steeper than 35 degrees until the snowpack has time to adjust to the added load.

Problemi valanghivi

  • Storm Slabs

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

    You could trigger a slab avalanche in the recent storm snow. Observers found varying amounts of reactivity on steep slopes, some of which were unaffected by wind. Wind will increase the hazard as you climb in elevation. Textured surfaces, pillows of recently drifted snow and new cornice development are signs that wind has deposited more snow onto a slope which will make the slope more reactive. With recent uncertainty, make conservative travel decisions and stay off slopes steeper than 35 degrees. 

    A small storm slab avalanche

Avalanche Discussion

A stout December 9 crust formed over our existing snowpack last week after 2 inches of rain fell. Avalanches are currently limited to the 2 feet of new snow above the crust, which will continue to grow in the coming days.  Below 4000ft the snowpack is thin, so watch out for open creeks, trees and rocks.  

In the Stevens Pass area weak sugary snow was found in the  layer above the December 9 crust. Surface hoar from Dec 12 was found overlying that in some spots.  There is a lot of uncertainty about these weak layers’ reactivity and how widespread it is. To investigate you can dig down easily through the layers above the crust to see if there is a horizontal stripe of large feathery crystals, or a broader swath of loose sugary grains closer to the crust. If you find either of these give steep slopes in the area a wide berth.

Regioni coperte