Bollettino valanghe

Northwest Coastal

Mar 13 – 14, 2016Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 11 years ago

Pericolo valanghe

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

In sintesi

The likelihood of triggering an avalanche will increase with the snow and wind forecast for Monday.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–4
    New wind slabs are expected to form through the day on Monday and may become more reactive with daytime warming and/or sun exposure.

  • Cornices

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–5
    Cornices are large and weak. I wouldn't linger on any alpine slopes with overhead hazard nor would I venture too close to ridge edge.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    3–6
    A layer of buried surface hoar or facets down 70-100cm has recently been reactive around Stewart and north.  An old weak crust layer down over 1m is still a concern in the south of the region.

Weather Forecast

MONDAY: snow starting overnight with 10-15cm expected by the end of the day, light to moderate southwesterly winds, 1000m freezing level. TUESDAY: light to moderate snowfall continues, moderate to strong westerly winds, 800m freezing level. WEDNESDAY: flurries, light and variable winds, 800m freezing level.

Avalanche Summary

New snow may cover lingering wind slabs that are still be reactive to human triggering on Monday. Several natural and artificially triggered cornice collapses in the last week have caused large avalanches in the alpine. On Thursday, a natural size 3.5 persistent slab avalanche was reported in Bear Pass. This avalanche occurred on a northwest aspect at 1350m elevation and released on the late-February surface hoar layer.

Snowpack Summary

Ongoing light snowfall and southerly wind have formed hard or soft wind slabs at treeline and in the alpine. Moist snow can be found at lower elevations and on solar aspects. A layer of surface hoar or facets down 70-100cm can be found in areas north of Stewart sitting below Marchs accumulated storm snow. Recent avalanche activity suggest that we may be approaching a critical load on this interface. An older crust/facet layer buried in early February can now be found around 80-120 cm below the surface although this layer has been dormant recently. Cornices are reported to be large and fragile.

Regioni coperte