Avalanche forecast

Northwest Coastal

Dec 20 – 21, 2014Avalanche Canada
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Avalanche danger

Mon
Tue
Alpine
4 · High
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

New snow and strong winds continue to develop storm slabs resulting in High avalanche danger.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    1–4
    The new storm slab is expected to continue to develop at higher elevations where precipitation continues to fall as snow.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2
    Rain on snow may occur as the freezing levels rise resulting in loose wet snow releasing from steep terrain features at lower elevations.

Confidence

Poor - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

Strong Southwest winds overnight combined with 10-15 cm of new snow and freezing level around 800 metres. Winds becoming moderate Southwest on Sunday as another 5-10 cm of snow is forecast. Winds becoming moderate Westerly on Monday with a few more cms during the day. Drying out and cooling down overnight, followed by another pulse of moisture on Tuesday afternoon.

Avalanche Summary

No new avalanches reported. The forecast new storm is expected to increase avalanche activity over the next few days.

Snowpack Summary

A new storm slab is developing above the recent mix of surfaces which include wind slabs in alpine terrain, hard rain crusts at lower elevations and weak surface hoar crystals. Last week's heavy rain affected southern parts of the region up to alpine elevations, while the far north remained drier and generally has a weaker snowpack. Areas which previously received rain have probably now formed a hard frozen crust. Upper elevation terrain and far northern areas are likely to have wind slabs and large fragile cornices. Deeper in the snowpack, weaknesses such as the mid-November crust-facet layer still exist. Avalanches at this interface have become unlikely, although the consequences of a release remain high. This layer may be more sensitive to triggering in steep, unsupported high alpine terrain, or in the far north of the region.

Regions covered