Avalanche Forecast

Issued: Feb 29th, 2024 4:00PM

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

Avalanche Canada swerner, Avalanche Canada

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Dangerous avalanche conditions continue. Natural and human-triggered avalanches are likely.

Stick to simple, non-avalanche terrain without exposure to overhead slopes.

Summary

Confidence

Moderate

Avalanche Summary

On Wednesday, a remotely triggered size 2 avalanche was reported at 1200 m. The crown was 60-100 cm deep. Explosive control produced avalanches that terminated approx. 200 m above the road. Observation details are obscured due to limited visibility.

Remotely triggered persistent slab avalanches were reported up to size two in the region early this week. This is a clear sign the persistent weak layer is primed for human-triggering.

Avalanche danger remains high on Friday

Snowpack Summary

40 to 70 cm of storm snow overlies wind-affected surfaces and old wind slabs in exposed areas and settling snow in sheltered areas.

Multiple weak layers exist in the upper and mid snowpack. The most concerning weak layer is a widespread crust down 30 to 100 cm with a weak layer of facets or isolated surface hoar above this crust. This problematic layering is very concerning with recent large avalanche activity attributed to it. Although natural avalanche activity may taper out on this layer as the snow stops falling it will remain possible to human-trigger it for some time afterward.

Weather Summary

Thursday Night

Cloudy with clear periods and snow 5 to 10 cm. Ridgetop wind 15 gusting to 65 km/h southwest ridgetop wind. Treeline temperature -10°C. Freezing levels valley bottom.

Friday

Cloudy with isolated flurries. Mostly light winds occasionally gusting to 60 km/hr. Treeline temperature -9°C. Freezing level valley bottom.

Saturday

Cloudy with sunny periods and isolated flurries. 10 to 25 km/h south ridgetop wind. Treeline temperature -9 °C. Freezing level valley bottom.

Sunday

Cloudy with sunny periods and isolated flurries. Light southeast ridgetop wind. Treeline temperature -9 °C. The freezing valley bottom.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • 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.
  • Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
  • Brief periods of sun could quickly initiate natural avalanche activity.

Problems

Persistent Slabs

An icon showing Persistent Slabs

A problematic weak layer from early February, of facets overlying a crust, is becoming increasingly triggerable. This layer was the culprit of recent human-triggered avalanches in the region.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1.5 - 3

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

Likely - Very Likely

Expected Size

1 - 2

Valid until: Mar 1st, 2024 4:00PM

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