Avalanche Forecast

Issued: Mar 18th, 2020 4:00PM

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

Avalanche Canada JMackenzie, Avalanche Canada

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Please make conservative choices. Now is not the time for an accident. The current pandemic is overloading the medical system and could affect backcountry rescue response.

Summary

Confidence

High -

Weather Forecast

A mix of sun and cloud on Thursday with occasional very light flurries. Winds will be light and variable.Temperatures should reach -7 in the Alpine. More of the same is expected Friday and Saturday.

Avalanche Summary

Several new naturally triggered avalanches occurred on the east side of the region (Mt Lawson, Mt Kidd) in the past 24 hours. These slides were up to size 2 and were in the alpine on east aspects.

Snowpack Summary

5cm of new snow fell overnight at treeline, but only a trace was recorded in valley bottoms. This new snow overlies a sun crust on solar aspects and previously formed wind slabs everywhere else. These buried wind slabs are found at all elevations and extend into open areas all the way to valley floor. The slabs are failing at a depth of about 20cm, which is making for generally poor quality skiing. Cornices are larger than normal. Although they haven't been active recently, any corniced area or slopes below should be avoided.

Terrain and Travel

  • Avoid convexities, steep unsupported terrain and rocky outcroppings.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Avoid exposure to slopes that have cornices overhead.
  • Be aware of the potential for large avalanches due to the presence of a deep persistent slab.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs seem to be everywhere. They are most concerning for human triggering in steep, convex and unsupported terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The deep persistent layer is still a concern, especially in shallow snowpack areas. A large cornice trigger could also be enough to weak up this layer.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1.5 - 3.5

Valid until: Mar 19th, 2020 4:00PM