Bollettino valanghe

South Coast

Mar 21 – 22, 2015Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 12 years ago

Pericolo valanghe

Mon
Tue
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
1 · Debole
Apri la mappa completa

In sintesi

The current snowpack structure is atypical for this region, especially at this time of year. Check out this blog post for more details: http://www.avalanche.ca/blogs/VQxmdCUAAJZDmnXn/rainsnowwind

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–4
    In the past week, people have remotely triggered large persistent slab avalanches. The spotty nature of this interface makes it difficult to manage. New snow has now overloaded this weak layer with the potential for surprisingly large avalanches.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–3
    The recent storm has created dense slabs which should gain strength fairly quickly. That said, I'd remain cautious of triggering large avalanches in higher elevation lee terrain. Cornices formed by the storm may also be large and weak.

Confidence

Fair - Due to the number of field observations

Weather Forecast

A ridge of high pressure will form on Sunday delivering a mix of sun and cloud. By Sunday afternoon, an unstable air mass will bring intermittent convective snowfall which should result in light to locally moderate accumulations for the rest of the forecast period. Ridgetop winds should remain generally moderate from the southwest with daytime freezing levels hovering around 1500m.

Avalanche Summary

Over the past week, isolated slab avalanches to size 2 have occurred on persistent weaknesses buried on March 11th. In a few cases, avalanches failed with light inputs such as remote triggers from distances of up to 100m away. New snow and wind has created its own mix of reactive surface instabilities, but it has also added load to these deeper, more destructive layers. There's a fair bit of uncertainty as to how the March 11th interface will react to storm loading. That said, I'd resist heading into aggressive higher elevation as any avalanches on this layer would likely be destructive in nature.

Snowpack Summary

New storm slabs have formed in response to steady wind, snowfall and warm temperatures prior to the weekend. At lower elevations, rain has saturated the snowpack. Cornices may also be fragile. A touchy crust/facet persistent weak layer, buried up to 70 cm down, has started to play up in isolated terrain, especially in the north of the region (see avalanche summary). Avalanche problems associated with this layer may linger for a while with the potential for surprisingly large and destructive avalanches. Below this, the snowpack is reported to be generally well-settled and strong.

Regioni coperte