Bollettino valanghe

Kootenay Boundary

Feb 18 – 19, 2012Avalanche Canada
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Archiviato · scaduto 15 years ago

Pericolo valanghe

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

In sintesi

We're in an incremental loading pattern--avalanches have just started to run on the early February weak layer. Check the Forecaster Blog for further discussion.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–4
    New wind slabs have developed on exposed lee terrain. The underlying snow surface makes a poor bond to newly forming wind slabs.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely - Very Likely
    Dimensione
    1–4
    New snow could overload a weak layer buried 30-40 cm below the surface.

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    3–7
    Large avalanches remain a concern in shallow rocky areas where they could be triggered with a very heavy load, such as cornice fall.

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain

Weather Forecast

A moist, northwesterly airflow has set up over the region, bringing a series of weak pulses of precipitation over the next few days. Snow amounts look to be in the region of 2-4 cm each day for Sunday, Monday and Tuesday. A more punchy storm is currently forecast for Tuesday night, which may bring more like 10-15 cm. Freezing levels from now until Tuesday afternoon will hover between 500-1000 m. Winds should stay mostly light or moderate, blowing from the west or northwest.

Avalanche Summary

Snow amounts over the early Feb weak layer reached threshold in many places on Saturday. Natural avalanches were observed in the storm snow to size 1.5. Avalanche control at Kootenay Pass produced avalanches up to size 2 running on a crust buried around 35 cm below the surface.

Snowpack Summary

Saturday's storm brought around 15 cm new snow, bringing the gradually incrementing snow amounts above the early Feburary surface hoar layer to around 30 cm. Alpine winds have been strong enough to blow snow around and touchy wind slabs have formed predominantly on northerly and easterly aspects. The early February weak layer comprises large surface hoar on sheltered aspects, facets on northerly aspects and a crust on solar aspects. In shallow snowpack areas concerns remain for the mid-December persistent weakness down around 80-100cm and for basal facets. Treeline snowpack depths are approximately 230 cm.

Regioni coperte