Bollettino valanghe

Northwest Coastal

Dec 27 – 28, 2015Avalanche Canada
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Archiviato · scaduto 11 years ago

Pericolo valanghe

Tue
Wed
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
Apri la mappa completa

In sintesi

Touchy conditions are expected. If you have questions about the snowpack, conservative terrain selection is always the answer.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    2–4
    A few buried surface hoar layers exist in the top 100cm of the snowpack. I would keep these on my radar on steep unsupported slopes, especially at treeline and below.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–3
    Up to 40cm of new storm snow overlies a weak mix of facets and surface hoar. I'd be extra cautious in wind-affected areas where the new snow exists as a cohesive slab. Touchy conditions should persist for the forecast period.

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

A dry ridge of high pressure is expected to develop for the forecast period. Expect increasingly clear skies and light ridge top winds. Alpine temperatures are expected to remain between -14 and -20.

Avalanche Summary

Due to inclement weather, observations were generally limited on Saturday, but a widespread storm slab cycle to size 2 was observed in the north of the region. Natural avalanche activity will likely taper-off with forecast clearing. However, human-triggered avalanches will remain a concern for the forecast period, especially at elevations or in parts of the region where recent storm accumulations have settled into a cohesive slab.

Snowpack Summary

Between 25cm and 40cm of new snow fell on Friday night and Saturday. Winds associated with the storm were highly variable. In areas (or at elevations) where the wind was strong, there may be a cohesive and reactive storm slab. In areas where the winds were light, you're more likely to find loose powder. The new snow overlies a touchy layer of sugary faceted snow and well-developed surface hoar which is reported to exist on all aspects and elevations. Due to the persistent nature of these underlying crystals, newly formed storm slabs may remain reactive for the foreseeable future. Adding to the mix of weaknesses in the upper snowpack are a few other surface hoar layers that developed throughout December and late November which you may now find buried in the top 100cm. The weight of the new snow (or a surface avalanche in motion) may cause these layers to "wake up" resulting in larger, more destructive avalanches.

Regioni coperte