Bollettino valanghe

Cariboos

Jan 11 – 12, 2013Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 14 years ago

Pericolo valanghe

Sun
Mon
Alta quota
2 · Moderato
Limite del bosco
3 · Marcato
Sotto il limite
3 · Marcato

In sintesi

Conditions will be tricky to manage this weekend, as a touchy surface hoar layer is buried only on some slopes and not others. Make constant snowpack assessments as you travel and take a cautious approach to terrain selection.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–5
    Recent winds have shifted snow into wind slabs which could fail with the additional weight of a person or snowmobile.
  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–5
    Storm snow is particularly reactive where it overlies buried surface hoar. This weakness may be triggered easily, or even from a distance. Avalanches could be surprisingly large.

Confidence

Fair - Due to variable snowpack conditions

Weather Forecast

Saturday: Light W wind. Alpine temperature near -15. Trace of snow.Sunday: Light NW wind. Alpine temperature near -14. No snow.Monday: Light W wind. Alpine temperature near -10. Light snow.

Avalanche Summary

A natural cycle of size 1-2.5 storm slabs occurred over the last few days. Skiers also triggered avalanches up to size 2, failing on buried surface hoar or facets. The touchy nature of the buried surface hoar has been revealed by skier-remote triggered avalanches, and a skier-triggered size 1 which ran across a flat bench and triggered a size 2 on another slope. These events were in the 1350-1450m elevation band on N/NE aspects in the south of the region.

Snowpack Summary

New snow has developed into slabs, with a weak bond to old snow surfaces including surface hoar (found especially below about 1600 m in sheltered areas) and facets. Variable amounts of storm snow (25-90 cm) fell across the region, leaving the buried surface hoar at a prime depth for human-triggering. Recent winds have left wind slabs in the lee of terrain breaks such as ridges and ribs at alpine and treeline elevations. In areas sheltered from the wind, fast-moving sluff could throw you off your feet or carry you into a terrain trap. A strong mid-pack overlies a weak facet/crust layer near the base of the snowpack.

Regioni coperte