Bollettino valanghe

Northwest Coastal

Dec 24 – 25, 2015Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 11 years ago

Pericolo valanghe

Sat
Sun
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Apri la mappa completa

In sintesi

Get out and enjoy the good riding conditions for Christmas before conditions change dramatically with the arrival of a powerful storm this weekend.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    1–3
    Variable winds have formed stubborn old slabs in lee features on east through northwest aspects at higher elevations.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    2–5
    A couple of buried weak layer of surface hoar should be on your radar. I would be suspicious of steep unsupported slopes at tree-line unless I knew the overlying snow had no slab properties, or that the weak layer does not exist in that location.

Confidence

High

Weather Forecast

We're looking at a brief clearing on Christmas before a powerful storm hits the north coast. Snow should start falling overnight on Friday. Coastal regions will see up to 30cm by Saturday evening, another 20cm overnight, with intense snowfall continuing into Monday resulting in total forecast storm amounts of up to 60cm.  Terrace will see slightly less, with 20cm expected Saturday and 50cm through the storm.  An artic front just inland will keep thing cool and freezing levels are expected to stay below 500m.   Strong to extreme south west winds are going to hit the coast on Saturday morning and will persists through the forecast period.

Avalanche Summary

No recent avalanche have been reported.

Snowpack Summary

Cool temperatures have been encouraging faceting in the upper snowpack, breaking down any storm slab that previously existed. Winds have been light and variable for the last week although reports from the field indicate there is lingering wind effect in the alpine or at tree-line. 25-40 cm of low density snow sitting above the December 17th surface hoar, and 35-55 cm above the December 14th surface hoar. Snow pit tests earlier in the weak produced sudden failures on both of these layers, however, it sounds like the overlying slab properties have subsequently changed. The December 1st surface hoar is now down a meter or so however, distribution and sensitivity of this layer is variable. In some areas, it may still be sensitive to human triggering and capable of wide propagations, in other areas it is non-existent or has gained significant strength.

Regioni coperte