Bollettino valanghe

Elkhorns

Wallowa Avalanche Center
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Pericolo valanghe

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

In sintesi

New snowfall along with moderate to strong southwest winds have formed fresh, sensitive windslabs on leeward ridgelines and cross loaded terrain features that could be sensitive to a person or machine.  This new snow and wind blown snow has fallen on either the solstice rain crust or pockets of windblown snow that fell on last tuesday (12/22).  Although the chances may be becoming less likely, there is still the possibility to impact a deeper slab that could fail on weak sugary snow that is buried up to 2-3 feet in the snowpack.  You would not want to tango with an avalanche failing into this old weak snow.  

Problemi valanghivi

  • Wind Slabs

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

    With arrival of the new snow and sustained winds out of the southwest yesterday afternoon and throughout the night, our main avalanche concern will be windslabs.  Observe localized wind loading patterns and avoid slopes that look like they have smooth and rounded surfaces.  Utilize small inconsequential test slopes to test the reactiveness of these windslabs.  

    Before the snow began to fall around 1300 hrs yesterday, the winds were the main attraction.  A short ski tour from Anthony Lakes revealed a greater challenge to find soft riding conditions than had existed the day before.   The obvious wind transport of snow  was creating isolated, very stiff, and stubborn wind slabs along ridgelines.  The lack of snow in the trees and variable snow surface conditions (see pictures) made the incoming storm a welcome sight.  

    Wind Transport of snow in the Northern Elkhorns

  • Persistent Slabs

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

    A less likely but much more consequential avalanche problem that we are still dealing with is the interface of very weak, sugary snow that can be found 2-3 feet down.   This interface was buried during the second weak of December.  Snowpack tests reveal that propagation is likely if this layer is impacted.  The Solstice Rain Crust (SRC) is helping to keep us from impacting this layer where it is thick enough to support the weight of a person and/or machine.  If you notice that you or your machine is breaking through the SRC and find yourself in snow above your knees, you are more likely to affect this weak layer.  If that is the case, best to avoid any slopes steeper than 30 degrees.   See the associated video that explains this further.

    If unfamiliar with dealing with this type of avalanche problem, a rider should always default to choosing simpler, lower angle, less consequential terrain in which to ride or travel.  

Regioni coperte