Avalanche forecast

Northwest Coastal

Feb 19 – 20, 2022Avalanche Canada
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Avalanche danger

Mon
Tue
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low

Highlights

At upper elevations where dry snow exists, storm slabs may remain sensitive to human triggers especially in wind loaded terrain features.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1.5–2.5

    Recent snow and wind have formed thick slabs over a slippery, thick rain crust. These storm slabs may remain reactive to human triggers on Saturday, particularly in wind loaded areas.

Confidence

Moderate -

Weather Forecast

Friday night : Snowfall 10-20 cm, strong, southwest wind, alpine temperature around -1, freezing level 1000 m.

Saturday: Mostly cloudy with flurries up to 5 cm, moderate west wind, high of -1, freezing level 800 m.

Sunday: Mostly cloudy with sunny periods, light to moderate northwest wind, high of -2, freezing level 600 m.

Monday: Sunny, moderate northeast wind, high of -10, freezing level valley bottom.

Avalanche Summary

On Thursday, natural loose wet activity was observed around Shames up to size 2. Skier and explosive triggered storm and wind slabs were also reported size 2.

 

Snowpack Summary

30-50 cm of heavy, moist snow from the recent storm will freeze from the surface down as freezing levels drop over the weekend. Below the recent storm snow, a widespread 10-30 cm thick rain crust at all elevations makes human triggering of avalanches on weak layers deeper in the snowpack very unlikely.

However, cornices overhead are a primary concern during sunny, warm, or windy conditions. Cornice failures can trigger very large persistent slab avalanches that would otherwise be difficult to human trigger.

Terrain and Travel

  • Keep in mind that human triggering potential persists as natural avalanching tapers off.
  • Start with conservative lines and watch for clues of instability.
  • Investigate the bond of the recent snow before committing to your line.
  • Stay off recently wind loaded slopes until they have had a chance to stabilize.
  • A crust on the surface will help bind the snow together, but may make for tough travel conditions.

Regions covered