Avalanche forecast

Northwest Coastal

Nov 21 – 22, 2015Avalanche Canada
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Avalanche danger

Mon
Tue
Alpine
No rating
Treeline
No rating
Below
No rating
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Highlights

Snowfall and extreme winds are expected to increase the Avalanche Danger. Conservative terrain selection is highly recommended. Forecasters are working with very little field data at this time. Please share you observations on the MIN.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–4
    The avalanche danger will rise with extreme winds and new snow. Human triggering will remain a concern on Sunday with the potential for large and destructive avalanches.

Weather Forecast

Throughout Sunday we can expect a clearing trend with freezing levels eventually falling to valley bottom. Extreme westerly winds are also expected to shift to moderate and northwesterly as a dry arctic ridge develops for Monday and Tuesday.

Avalanche Summary

A natural avalanche cycle is expected to occur in response to new snow and wind on Saturday. On Sunday, natural avalanche activity is expected to taper-off with forecast cooling and clearing. That said, the newly formed storm slab may remain ripe for human triggering for the next few days.

Snowpack Summary

Deep and destructive storm slabs are expected to form as a result of Saturday's storm, especially in the north of the region where total accumulations are expected to be the highest. The reactivity of these new storm slabs will likely change with elevation and underlying snowpack structure. Due to limited observations, I have very little confidence in what that underlying structure may be, although faceting and surface hoar development have been reported on shaded terrain. If you've been in the mountains, please share your observations on our Mountain Information Network.

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