Bollettino valanghe

East Slopes North

Northwest Avalanche Center
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Pericolo valanghe

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

In sintesi

You may be able to trigger small avalanches at upper elevations where the wind drifts the new snow.  Look out for plumes of blowing snow and pillow-like slabs of snow below ridges. On Tuesday, just enough new snow and wind will maintain heightened conditions on the highest elevation slopes.

Problemi valanghivi

  • Wind Slabs

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

    If you find signs of instability, like cracks shooting through the snow or wind drifts that break easily with a person's weight, stay off of leeward slopes over 35 degrees. Look for visual clues like sharp wind drifts and stiffer snow surfaces. Steer around fresh drifts and stick to lower-angle or wind-sheltered slopes. 

    Another shot of snow and southeasterly wind will maintain wind slab avalanche conditions at the highest elevations. Wind slab avalanches are possible near and west of Washington Pass, where snow accumulations could be deepest. To the east, avalanches may be less likely. Older slabs that formed on Friday will now be difficult to trigger.

    (12/22/2023)

    Cracks in recently wind transported snow near Harts Pass.

    Photo: Willie Webster

Avalanche Discussion

On Monday, observers on the flanks of Silver Star Mtn reported light graupel accumulation and minimal blowing snow. They triggered very small, minor loose avalanches with ski cuts. On Friday, observers in the Harts Pass and Willow Creek areas noted significant blowing snow, fresh wind features (6-8" deep), and cracks in the new snow.

Recent snow from the past week fell on a variety of old surfaces. Surface hoar was seen particularly on shaded aspects. On the 20th, observers on Rainy Pass found it on the surface as well as buried in the top 8" of the snowpack. In steeper, more southerly terrain, a surface crust likely formed. Since these layers were buried, we haven't received any reports that they are currently problematic. As you travel, take note of older snow layers by using small hand pits.

Similarly, you can find older layers of buried surface hoar, the 12/10 crust (below ~6000ft), and the more prominent 12/7 atmospheric rain crust in the upper snowpack across the terrain.

Regioni coperte