Bollettino valanghe

Purcells

Mar 17 – 18, 2012Avalanche Canada
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Archiviato · scaduto 15 years ago

Pericolo valanghe

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

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible - Likely
    Dimensione
    2–5
    The new snow arrived with light-moderate winds and settled into a soft slab. Old windslabs may be hidden by the soft new snow.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely - Very Likely
    Dimensione
    4–8
    The deep nature of the mid-February surface hoar layer makes potential avalanches triggered on this layer large and destructive. Regular and ongoing avalanche activity associated with this layer indicates it is very much still alive.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Very Likely
    Dimensione
    2–6
    Storm slabs continue to build and consolidate. The dense storm slab may be easily triggered by light additional loads. Solar radiation may trigger another round of natural activity.

Snowpack Summary

Another 5-10 cm of new snow overnight combines with the 30-40 cm of snow on Friday morning to form a soft slab that is sitting on the recent storm snow. The combined slab above the mid-february persistent weak layer is now between 150-200 cm. Some operators continue to get easy-moderate sudden planar character shears on the mid-february surface hoar in shallow areas. The persistent weak layer continues to be a concern at all elevations, and may show wide propagations on low angle terrain below treeline. The new snow may consolidate and release naturally if the skies clear and we get some strong solar radiation. Snowpack conditions continue to be tricky to evaluate, and are variable throughout the region.

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Sunday

Weather Forecast

There are remnants of a system moving up from south of the border that may bring some moisture into the South Columbia mountains on Saturday night. Unsettled conditions are expected across the Interior regions again on Sunday. Some areas may see periods of heavy convective flurries, while others may see broken skies or scattered cloud. Winds should stay mostly light from the south, and the freezing level is expected to drop to the valley bottom Saturday night and then rise to about 800 metres on Sunday. Monday is forecast to be unsettled again, but with more likelihood of sunny periods. A Pacific frontal system is expected to start moving in from the coast on Tuesday bringing strong westerly winds and heavy precipitation.

Avalanche Summary

Explosive control work on Friday resulted in slab avalanches on various aspects up to size 3.5. There was one report of a natural avalanche size 3.5 that may have run Thursday afternoon or evening.

Regioni coperte