Avalanche Forecast

Issued: Dec 25th, 2022 4:00PM

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

Avalanche Canada rbuhler, Avalanche Canada

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Ongoing wind slab formation is expected to continue on Monday. These wind slabs likely sit over a weak layer which may increase their size and reactivity. Extra caution and conservative terrain selection are recommended at higher elevations.

Summary

Confidence

Low

Avalanche Summary

No new avalanches were reported on Saturday.

On Friday afternoon, the Avalanche Canada field team reported ski-cutting a few size 1 avalanches on a north aspect convex roll feature at 1600 m elevation in the Hankin-Evelyn area. These failed on the old, hard surfaces and encompassed up to 25 cm of the recent storm snow.

Snowpack Summary

The new snow has buried a highly variable surface from the recent period of cold temperatures and outflow winds. The old wind-affected surface was generally very hard and in many places, the snow had been stripped to the ground. In sheltered areas around treeline, faceting had been observed and the snow surface was becoming unconsolidated.

Prior to the new storm snow, a layer of surface hoar could be found down 20 to 30 cm at treeline but had not been an active layer of concern.

Generally, the snowpack is shallow and highly variable in terms of depth, with the mid and lower snowpack presenting as settled and dense.

Weather Summary

A series of warm Pacific storm systems continue to impact the coast but only limited amounts of precipitation are forecast to push into the inland regions. However, some of the warm air has reached the interior with a temperature inversion in the valleys.

Sunday night

Snowfall 5-10 cm, moderate to strong S-SW wind, freezing level generally at valley bottom with some warmer air potentially sitting around 1500 m.

Monday

Snowfall 5-10 cm, moderate to strong S-SW wind, freezing level generally at valley bottom with some warmer air potentially sitting around 1500 m.

Tuesday

Mainly cloudy with a chance of sunny breaks, light to moderate E wind, treeline high around -6 °C.

Wednesday

Mainly cloudy with a chance of both sunny breaks and isolated flurries, moderate SW wind, treeline high around -8 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • The best and safest riding will be on slopes that have soft snow without any slab properties.

Problems

Wind Slabs

An icon showing Wind Slabs

New wind slabs have formed as recent and ongoing snowfall continues to be redistributed by strong southwest winds. Where these new wind slabs overlay a weak layer of sugary facets, increased reactivity should be expected and the slabs may propagate wider than normally expected. Mild temperatures in parts of the region may also be increasing the reactivity of newly formed wind slabs.

Older hard wind slabs from last week's northeast outflow wind event may still be reactive, but this is likely becoming an isolated problem. However, it is safest to assume wind slabs could exist on all aspects in wind-exposed terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Valid until: Dec 26th, 2022 4:00PM