Bollettino valanghe

South Rockies

Jan 31 – Feb 1, 2012Avalanche Canada
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Archiviato · scaduto 15 years ago

Pericolo valanghe

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

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible - Likely
    Dimensione
    1–4
    Stiff wind slabs have formed on North through East aspects. They may be found lower on slopes in unusual places due to the strong winds. Wind slab avalanches are likely reactive to rider triggers.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–3
    The region received up to 30cms of new snow Sunday night. Storm slabs are reported to be touchy to rider triggers.

Confidence

Fair - Freezing levels are uncertain on Friday

Weather Forecast

Snow amounts near 5cms Tuesday night, accompanied by strong SW winds. Wednesday: Dry conditions with sunny breaks. Ridgetop winds 30-50km/hr from the West. Freezing levels 1300m. Thursday: Mix of sun and cloud. Ridgetop winds 20km/hr from the North. Freezing levels valley bottom. Friday: Ridgetop winds switching back to SW later in the day. High pressure dominating the province will bring warm air and rising freezing levels to the region.

Avalanche Summary

No new natural avalanches reported today. On Monday skier controlled, and explosive controlled avalanches were initiated up to size 2 with crown depths being 30-40cms.

Snowpack Summary

The freezing level was as high as 1500m Sunday; as a result, a lot of precipitation that fell on Sunday was rain. Sunday night the region received near 30cms of new snow. Strong SW winds created stiff, yet reactive wind slabs on lee slopes. Cross-loading, and wind slabs are also found lower on the slopes and in unsuspecting terrain due to the strong push of the winds. Storm slabs have also developed at all elevations, and are reported to be touchy to rider triggers. So far the new wind slab and storm slabs are only releasing in the upper 30-40cms of the snowpack, with nothing stepping down lower. Below 1700m a 4cm thick crust exists, I suspect it's from the rising freezing levels, and precipitation last Sunday. This crust is said to be supportive. Deeper in the snowpack, a surface hoar layer buried in early December remains a concern, as avalanches triggered on this layer would be destructive. This is a low probability/high consequence scenario. Down deeper, at the bottom of the snowpack basal facets exist in many parts of the region. On January 27th a sledder triggered avalanche occurred, releasing in the basal facets.

Regioni coperte