Avalanche Forecast

Issued: Apr 3rd, 2024 4:00PM

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

Avalanche Canada MW, Avalanche Canada

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The upper snowpack has undergone significant settlement over the past few days. Be on the lookout for freshly formed wind slabs and avoid overhead cornice exposure.

Summary

Confidence

Moderate

Avalanche Summary

Numerous natural size 1-1.5 wet loose avalanches observed on the Icefields Parkway on Tuesday.

No new avalanche activity on the Icefields Parkway or Maligne Lake Road Today.

Snowpack Summary

5-10cm of new snow overnight on Tuesday arrived with strong to extreme SW wind building winds slabs at treeline and above. A total of 20-40cm of snow now sits over the March 19th crust which is present everywhere except North aspects above 1900m. Solar aspects have multiple crusts within the upper 30 cm. The Feb 3rd crust interface is down 30-90cm. Basal depth hoar and facets make up the bottom of the snowpack. HS ranges from 50 to 150cm.

Weather Summary

Thursday Mainly cloudy with isolated flurries. Trace precipitation. Wind east: 15 km/h gusting to 40. Freezing level at valley bottom

Friday Cloudy with sunny periods & isolated flurries. Trace precipitation. Wind light to 15 km/h. Freezing level 2000m

Saturday A mix of sun and cloud. Freezing level 2100m

Mountain Weather Forecast is available @ Avalanche Canada https://www.avalanche.ca/weather/forecast

Terrain and Travel Advice

  • Wind slabs may be poorly bonded to the underlying crust.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong to extreme SW wind has scoured ridgetop but wind slabs are forming low in start zones. If triggered, wind slabs could step down to the persistent slab.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

This problem seems to be most active where the March 19th crust is not supportive over the Feb 3rd weak layer (down 30-90cm) of facets over a crust. Northerly aspects between 1900-2400m seem to be the problem area.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 3

Cornices

An icon showing Cornices

Cornices have grown dramatically over the past two day and a drop in temperature may make them more reactive.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Apr 4th, 2024 4:00PM