Avalanche Forecast

Issued: Apr 11th, 2022 4:00PM

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

Avalanche Canada JSmith, Avalanche Canada

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Strong northeasterly winds have reverse loaded slopes below ridgetops. Recently formed wind slabs may be reactive to human triggers.

Use high points in the terrain such as ridges or ribs to avoid areas of wind-loaded snow. 

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Monday night: Clear / Moderate east wind / Low of -20 / Freezing level valley bottom.

Tuesday: Mix of sun and cloud / Light east wind / High of -7 / Freezing level valley bottom.

Wednesday: Mix of sun and cloud / Light southeast wind / High of -6 / Freezing level valley bottom.

Thursday: Sunny / Light east wind / High of -4 / Freezing level 1000 m.

Avalanche Summary

Two size 2 wind slab avalanches were remotely triggered by a helicopter from 100 m away on steep, north aspects at treeline on Sunday. The slabs were 80-100 cm deep.

Snowpack Summary

20-50 cm of recent snow buries a melt-freeze crust that exists on all aspects to at least 2000 m. A sun crust likely extends to mountain tops on solar aspects.

Recent strong winds from a variety of directions formed wind slabs on lee aspects at treeline and above.

The prominent layer in the upper snowpack is a melt-freeze crust down 60-80 cm.

Cornices are very large and exposure to slopes beneath them should be minimized, especially if the weather is sunny, warm, or windy.

Terrain and Travel

  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Caution around slopes that are exposed to cornices overhead.

Problems

Wind Slabs

An icon showing Wind Slabs

 Recent wind has varied in direction so watch for wind slabs on all aspects. 

Use high points in the terrain such as ridges or ribs to avoid areas of wind-loaded snow. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 12th, 2022 4:00PM