Avalanche Forecast

Issued: Feb 28th, 2024 4:00PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Storm Slabs and Persistent Slabs.

Avalanche Canada lbaker, Avalanche Canada

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Very dangerous avalanche conditions continue at higher elevations. Avoid all avalanche terrain.

Natural and human-triggered avalanche activity remains likely.

Summary

Confidence

Moderate

Avalanche Summary

By 4 pm on Wednesday, a widespread natural storm slab avalanche cycle was reported at all elevations up to size 1.5.

On Tuesday, operators in the region continued to observe evidence of numerous natural, large, persistent slab avalanches that likely released during the previous storm.

On Monday, numerous skier remotely triggered persistent slab avalanches were reported up to size 2. These avalanches occurred mainly on north and easterly aspects between 1600 and 2000 m.

Snowpack Summary

30 to 60 cm of storm snow overlies wind-affected surfaces and old wind slabs in exposed areas at all elevations.

Multiple weak layers exist in the upper and mid snowpack. The most concerning weak layer is found down 30 to 100 cm and is composed of a layer of facets or in isolated areas preserved surface hoar above a thick crust. This layer is the culprit of recent remotely-triggered avalanches in low-angle terrain. Professionals are concerned about how this layer will react to the new snow load.

Weather Summary

Wednesday Night

Cloudy with 20 to 30 cm of snow. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -9 °C. Freezing level drops to valley bottom.

Thursday

Mainly cloudy with 2 to 10 cm of snow. 10 to 25 km/h southwest ridgetop wind. Treeline temperature -8 °C. Freezing level hovers around 800 m.

Friday

Mainly cloudy with 3 to 10 cm of snow. 25 to 40 km/h south ridgetop wind. Treeline temperature -8 °C. Freezing level hovers around 800 m.

Saturday

Mainly cloudy with 1 to 3 cm of snow. 10 to 30 km/h south ridgetop wind. Treeline temperature -10 °C. Freezing level remains at valley bottom.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
  • Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
  • Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.

Problems

Storm Slabs

An icon showing Storm Slabs

Storm snow and strong winds have built touchy slabs at higher elevations. Deeper deposits are expected in north and east facing terrain around ridgelines. Investigate how the new snow is bonding to the underlying crust as you travel.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

A weak layer of facets or surface hoar above a thick crust persists in the snowpack. If triggered storm slab avalanches may step down to this layer resulting in very large, destructive avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1.5 - 3.5

Valid until: Feb 29th, 2024 4:00PM