Avalanche Forecast

Issued: Dec 26th, 2023 4:00PM

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

Avalanche Canada zryan, Avalanche Canada

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There are very few field observations coming from this forecast area. Submit a MIN if you head out!

Uncertainty around buried weak layers is best managed with conservative terrain choices.

Summary

Confidence

Low

Avalanche Summary

Over the weekend in the neighboring region to the east, many large (size 2 to 3) natural and rider triggered (some remotely triggered) persistent and deep persistent slabs were reported in the alpine and treeline.

We are unsure if the same deep persistent slab problem exists in this region, and this uncertainty is best managed though conservative terrain choices.

Moving forward, natural avalanche activity may taper, but large human-triggered slabs remain possible.

Snowpack Summary

Recent strong winds have created heavily wind-affected surfaces in the alpine and treeline. Below treeline a new crust is on or near the surface.

The mid pack contains several layers of note; a layer of surface hoar and a crust down 20 to 40 cm, a significant crust from the early December rain event down around 50 cm and a layer of surface hoar down 50 to 90 cm.

The make up of the lower snowpack is variable throughout the region, in shallower snowpack areas, basal facets may exist.

Weather Summary

Tuesday Night

Clearing. Southwest alpine wind 50 km/h dropping to 20 km/h. Treeline temperature -4 °C. Freezing level dropping to 500 m.

Wednesday

A mix of sun and cloud. South alpine wind 20 to 40 km/h. Treeline temperature -3 °C. Freezing level rising to 1400 to 2000 m.

Thursday

Cloudy with isolated flurries. Southwest alpine wind 20 to 50 km/h. Treeline temperature 0 °C. Freezing level 1000 to 1700 m.

Friday

A mix of sun and cloud with isolated flurries. South alpine wind 20 to 40 km/h. Treeline temperature -3 °C. Freezing level 2000 to 2500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Use careful route-finding and stick to moderate slope angles with low consequences.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent strong southerly winds have formed wind slabs on a variety of aspects in lee features in the alpine and treeline.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

A layer of surface hoar is down 50 to 90 cm and is still concerning where a significant crust is not found above it.

Weak basal facets may exist in some areas. This layer is most concerning in shallow alpine areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Dec 27th, 2023 4:00PM