Avalanche Forecast

Issued: Apr 20th, 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 JSmith, Avalanche Canada

Moderate southerly winds have formed wind slabs that may remain reactive to human triggers on lee features at treeline and above.

 Use 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

Wednesday night: Cloudy with flurries; 5-15 cm (rain below around 800 m) / Moderate southeast wind / Low of -3 / Freezing level 1100 m.

Thursday: Cloudy with flurries; 3-10 cm (rain below around 1300 m) / Light south wind / High of 2 / Freezing level 1600 m.

Friday: Mix of sun and cloud / Light west wind / High of 3 / Freezing level 1800 m.

Saturday: Mix of sun and cloud / Light west wind / High of 4 / Freezing level 1900 m.

Avalanche Summary

Skier and snowmobiler triggered storm slab avalanches up to size 2 were reported on Tuesday. North and easterly aspects that had been loaded by the wind at treeline and above were the most reactive. See MINs Here and Here.

We currently have very limited avalanche observation data from this region.

Please consider posting your observations to the Mountain Information Network (MIN). Photos of current conditions and avalanches are the most helpful. 

Snowpack Summary

5-15 cm of new snow Wednesday night will add to the 35-55 cm of recent snow. Moderate southerly winds have formed wind slabs that may remain reactive to human triggers on lee features at treeline and above.

The recent snow is sitting on a variety of hard snow surfaces, including crusts and wind scoured snow. Below this, there are several crusts in the upper snowpack, but they are unlikely to be a concern in most areas until the next significant warming event.

Terrain and Travel

  • Be especially cautious as you transition into wind affected terrain.
  • Use ridges or ribs to avoid areas of wind loaded snow.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Avoid exposure to slopes that have cornices overhead.

Problems

Wind Slabs

An icon showing Wind Slabs

Moderate southerly winds have formed wind slabs that may remain reactive to human triggers on lee features at treeline and above.

 Use ridges or ribs to avoid areas of wind loaded snow. 

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

An icon showing Cornices

Cornices may be weak and reactive to human triggers. They create a significant falling hazard, and may produce large slab avalanches as they fall onto the slope below.  

Cornice failures are more likely during hot and sunny weather.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Apr 21st, 2022 4:00PM