Bollettino valanghe

Mount Shasta

Mount Shasta Avalanche Center
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Pericolo valanghe

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

In sintesi

It remains possible to trigger a wind slab on north and east aspects near and above treeline. Steep slopes with overhung cornices, or dense textured snow warrant caution. Localized assessments and terrain choice are key for identifying and managing features of concern.

Problemi valanghivi

  • Wind Slabs

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

    Moderate to strong west and northwest winds have blown consistently over the past 24 hours. Easterly aspects sit in the cross-fire of the wind's path and subjected to wind loading. While drifts exist on south aspects, shady north and east aspects are where drifts will be largest and most reactive. Being the shortest days of the year, instabilities can persist longer than average. Clues like wind lips, cornices, scoured ridges lines, and dense wavy surface snow will point you in the direction of wind loading. In the right place with the right trigger, slabs breaking deeper than a foot remain a possibility. 

    You can manage this scenario by avoiding steep leeward slopes, and identifying features that encourage drifting, such as, chutes, gullies, rock bands, and pronounced ridgelines. Or, feel for yourself. Is the surface snow denser than the snow below? How cohesive is it? Can you initiate shooting cracks on small test slopes? These data points lead to better decision-making and problem identification in the backcountry. 

Avalanche Discussion

A Gray Butte outing yesterday found dry snow near treeline, with damp surface snow below treeline forming a thin surface glaze from moist air. Minor cracking was observed in the top 15 cm (7 inches) of wind blown snow on east and north aspects of Gray Butte. A small, < D1 size avalanche was observed off the east ridgeline. Sheltered west aspects held soft wind effected snow.       

The current reprieve in weather is lending its hand to a general trend in stability throughout the forecast zone. The snowpack has settled multiple inches, and fewer and fewer signs of instability exist. While jumping headfirst into the deep end still holds risk, stepping out cautiously and conservatively can be done. Looking forward, warm temperatures will contribute to snowpack stability, leaving wind as the main factor to cause avalanche danger.  

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