Avalanche Forecast

Issued: Apr 8th, 2021 4:00PM

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

Avalanche Canada astclair, Avalanche Canada

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Watch for newly formed wind slabs in drifted areas at upper elevations and minimize exposure to cornices. Be prepared to back off terrain if the snow becomes wet from strong sun. 

Summary

Confidence

Moderate - Uncertainty is due to how the snowpack will react to the forecast weather.

Weather Forecast

Thursday night: Clear, moderate southwest wind, treeline temperatures near -7 C, freezing level dropping to valley bottom.

Friday: Sunny with increasing cloud in the afternoon, moderate southwest wind, treeline temperatures near -2 C, freezing level rising to 1800 m and dropping to 1200 m.

Saturday: Mainly cloudy, 5-15 cm of snow, light west wind, treeline temperatures near -5 C, freezing level rising to 1400 m and dropping to valley bottom.

Sunday: Increasing cloud, light southwest wind, treeline temperatures near -1 C, freezing level rising to 1700 m and dropping to valley bottom.

Avalanche Summary

On Thursday, a few small (up to size 1.5) loose dry avalanches were observed.

Snowpack Summary

10-20 cm of recent snow has been accompanied with moderate southwest winds, forming fresh wind slabs in lee features that may be possible to human trigger. Cornices are large, looming, and capable of triggering avalanches when they fail.

The mid-pack is firm and well settled. Some faceted snow and a decomposing melt-freeze crust can be found near the base of the snowpack. Snow line is slowly creeping up the mountains to roughly 1400 m in elevation. Check out this MIN report for more details on the access from common staging areas.

Glide cracks releasing as full depth glide slab avalanches become more common in the spring and are extremely difficult to predict. Best practice is to avoid slopes with glide cracks.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid freshly wind loaded terrain features.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet

Problems

Wind Slabs

An icon showing Wind Slabs

 Recent snow and wind are expected to form fresh wind slabs that may be reactive to human triggering. Avoid freshly wind-loaded terrain features.  

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Cornices

An icon showing Cornices

Cornices are large and looming along many ridgelines. They are capable of triggering large avalanches when they fail.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 2.5

Loose Wet

An icon showing Loose Wet

Wet loose avalanches may be possible on steep slopes exposed to strong sun.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Valid until: Apr 9th, 2021 4:00PM