Avalanche Forecast

Issued: Feb 27th, 2024 4:00PM

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

Avalanche Canada lbaker, Avalanche Canada

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Very dangerous avalanche conditions exist at all elevations. Avoid all avalanche terrain.

Widespread natural avalanche activity is expected with heavy snowfall and strong winds.

Summary

Confidence

High

Avalanche Summary

On Monday, numerous skier remotely triggered persistent slab avalanches were reported up to size 2 in the region. These avalanches occurred mainly on north and easterly aspects between 1600 and 2000 m. A few remotely triggered windslab avalanches were also reported up to size 1 on north and south aspects at 1600 m.

Operators in the region also reported evidence of numerous natural, size 3, persistent slab avalanches that likely released during the previous storm.

Snowpack Summary

Storm snow accumulates over 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

Tuesday Night

Cloudy with 10 to 20 cm of snow. 25 to 40 km/h southwest ridgetop wind. Treeline temperature -13 °C. Freezing levels remain at valley bottom.

Wednesday

Cloudy with 20 to 40 cm of snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature rises to -6 °C. Freezing level rises to 1200 m throughout the day.

Thursday

Mainly cloudy with 1 to 2 cm of snow. 20 to 30 km/h southwest ridgetop wind. Treeline temperature rises to -8 °C. Freezing level hovers around 800 m.

Friday

Mainly cloudy with 2 to 8 cm of snow. 30 to 50 km/h south ridgetop wind. Treeline temperature rises to -8 °C. Freezing level hovers around 800 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
  • Storm slab size and sensitivity to triggering will likely increase through the day.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.

Problems

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

Storm Slabs

An icon showing Storm Slabs

As snow accumulates through the day watch for storm snow becoming a cohesive slab and increasingly reactive to triggers. Deeper deposits are expected in north and east facing terrain around ridgelines.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2.5

Valid until: Feb 28th, 2024 4:00PM