Bollettino valanghe

Soldier & Wood River Valley Mtns

Sawtooth Avalanche Center
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Pericolo valanghe

Thu
Alta quota
1 · Debole
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
Non aggiornato — questo bollettino è scaduto 7 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Most slopes are safe from avalanches today. LOW danger means triggering avalanches is unlikely but not impossible. Be on the lookout for areas where hard, wind drifted snow sounds or feels hollow or "drummy". On very steep slopes where these drifts overlie weak, sugary snow, they could still pose a problem—most likely above about 9000' in elevation. 

Problemi valanghivi

  • Persistent Slabs

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

    The last significant, reported avalanche in this zone occurred on February 6th when ski patrollers at Bald Mountain intentionally triggered the avalanche pictured to the right during mitigation work before opening the ski area. This avalanche failed on a wind-loaded slope that sees little ski traffic and harbored weak, sugary faceted snow in the lower part of the snowpack.

    This exact snowpack scenario—hard, wind-drifted snow overlying weak faceted snow—is where you're most likely to find unstable conditions today. While triggering a slab avalanche is unlikely, I'd still pay attention in very steep, recently wind-loaded terrain, especially at elevations over about 9000' in this zone.

    If your sled or skis are staying on top of a hard surface but the snow feels "punchy" or hollow, consider where even a small avalanche could carry you before riding that 40 degree slope.  

    Additional Discussion: Small, wet loose avalanches (photo below) are possible on slopes directly facing the sun. In recent days, several little wet slides released on west-facing slopes where the snowpack was only 12-18" thick. 

Avalanche Discussion

LOW does not neccessarily mean NO: Today is the first day of the year with LOW danger at all elevations in any of our zones. What is LOW avalanche danger? Most slopes are safe, but not all slopes are safe. If you dropped 50 people off on the highest peaks in this zone and told them to ski or ride the steepest wind-loaded slopes they could find, someone would probably trigger a slab avalanche. It's nearly impossible to definitively predict which slope(s) are "triggerable", but we can hedge our bets by thinking about the consequences of small avalanches where we're playing. If you don't like the looks of what's below you—trees, cliffs, roads or other terrain traps—then move to a different part of the slope or another area.

Today's canvas is tomorrow's problem: The recent spell of cool, sunny weather has created weak surface snow on some aspects and elevations. In mid-February in south central Idaho, the combination of the sun angle and cool, winter temperatures can produce excellent conditions for a process called near-surface faceting. At the snow surface, you'll notice a variety of crusts and "recycled powder" (facets) that sound and feel "hissy" when you're skiing or riding. If we get a decent shot of snow this weekend, we may see avalanche activity on relatively thin slices of the compass where the weak layer is "just right". Noting the variety of the snow surface today can help you wrap your head around how dramatically stability may change with minor changes in aspect or slope angle this weekend. 

 

Regioni coperte