Avalanche Forecast

Issued: Feb 19th, 2022 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs and Cornices.

Avalanche Canada ahanna, Avalanche Canada

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Slabs may remain triggerable at upper elevations where dry snow has been wind loaded into leeward terrain features. Watch for signs of instability like cracking and recent avalanches.

Summary

Confidence

Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.

Weather Forecast

Saturday night: Mostly cloudy with flurries up to 5 cm, moderate northwest wind, freezing level dropping to 500 m.

Sunday: A mix of sun and clouds with isolated flurries, light to moderate northwest wind, high of -2, freezing level 500 m.

Monday: Sunny, strong northeast wind, alpine high of -15, freezing level valley bottom.

Tuesday: Increasing cloud, light northwest wind, alpine high of -10.

Avalanche Summary

On Thursday and Friday, natural wet loose avalanches were reported up to size 2. Skier and explosive triggered storm and wind slabs were also reported size 2.

 

Snowpack Summary

30-50 cm of recent snow sits over a widespread 10-30 cm thick rain crust at all elevations. At upper elevations, the recent snow has been wind affected. At mid elevations, it may contain a thin rain crust. Below 1300 m, moist surfaces will refreeze as temperatures drop this weekend.

The thick rain crust beneath the recent snow effectively caps the underlying snowpack, making human triggering of avalanches on deeper weak layers very unlikely. However, cornice failures may still have potential to trigger these deeper weak layers, resulting in very large avalanches.

Terrain and Travel

  • Keep in mind that human triggering potential persists as natural avalanching tapers off.
  • Be careful as you transition into wind affected terrain.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Start with conservative lines and watch for clues of instability.
  • Extra caution is needed around cornices under the current conditions.

Problems

Wind Slabs

An icon showing Wind Slabs

Slabs may remain reactive to human triggers in wind-loaded terrain features like ridge crests and convexities.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Cornices

An icon showing Cornices

Large, looming cornices overhead are a primary concern during sunny, warm, or windy conditions. Cornice failures are dangerous on their own, but they also have potential to trigger large persistent slab avalanches that would otherwise be difficult to trigger.

Aspects: North, North East, East, South East, South, North West.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Feb 20th, 2022 4:00PM