Avalanche Forecast

Issued: Jan 5th, 2023 4:00PM

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

Avalanche Canada trettie, Avalanche Canada

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630 AM update: Continue to avoid high consequence terrain. New snow will be most reactive at wind-affected elevations. The new snow load adds stress to deeper instabilities, with potential for large, consequential avalanches.

Summary

Confidence

Moderate

Avalanche Summary

On Wednesday one size 1.5 ski cut was reported. It was a wind slab over the late December crust on a east aspect.

Snowpack Summary

Strong to extreme southerly winds will continue to scour south facing slopes. Thin wind slabs could be found a short ways into lee slopes but most snow will be sublimated or blown way by the intense winds. Moist snow will likely be observed at lower elevations.

In Sheltered terrain at treeline, a new layer of surface hoar is on or near the surface. A thick crust formed in late December is down 20 to 50cm. at lower elevations this crust is up to 15cm thick, in the alpine it is thin and breakable.

Near the base of the snowpack, a weak facet/crust layer from mid November can be found and is still a concern. In general the snowpack is weak, faceted and shallow.

Weather Summary

Thursday Night

Stormy with 5 to 15cm of new snow expected. Strong to extreme south winds. Freezing level falling to 1200m by early morning.

Friday

Cloudy with up to 5cm of new snow expected. Strong southerly winds. Freezing level rising to 1500m.

Saturday

Cloudy with around 5cm of new snow expected. Moderate southerly winds and freezing levels around 1500m.

Sunday

Cloudy with around 5cm of new snow expected. Strong southerly winds and freezing levels around 1500m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Dial back your terrain choices if you are seeing more than 20 cm of new snow.
  • Be especially cautious as you transition into wind affected terrain.
  • If triggered, storm slabs in-motion may step down to deeper layers and result in very large avalanches.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.

Problems

Storm Slabs

An icon showing Storm Slabs

New snow and wind are forming storm slabs.

Keep in mind that if triggered, storm slabs may step down to deeper layers resulting in very large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A crust with weak, faceted snow above and below exists near the base of the snowpack. Human-triggering this layer is unlikely, but large loads such as cornice fall or a smaller avalanche stepping down to this layer are possible. Avoid thin, rocky, wind-affected areas where triggering this layer is most likely.

This layer is likely to be a concern for an extended period in this region.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely

Expected Size

2 - 3.5

Valid until: Jan 6th, 2023 4:00PM