Avalanche Forecast

Issued: Dec 9th, 2019 4:00PM

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

Avalanche Canada shorton, Avalanche Canada

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Low hazard doesn't mean no hazard. Use caution in steep alpine terrain where wind slab avalanches could still be triggered.

Summary

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

MONDAY NIGHT: Partly cloudy, 60-80 km/h wind from the south, alpine temperature inversion breaks down overnight with freezing level dropping back to valley bottom.

TUESDAY: Increasing cloud with light flurries starting in the afternoon with up to 5 cm of new snow, 40 km/h wind from the south, alpine high temperatures around -2 C.

WEDNESDAY: Flurries increasing in intensity throughout the day with 5-10 cm possible by the afternoon, 60 km/h wind from the south, alpine high temperatures around -2 C.

THURSDAY: Snow with up to 30 cm along the coast and 10-15 cm further inland, 50 km/h wind from the south, alpine high temperatures around -2 C.

Avalanche Summary

Warm alpine temperatures resulted in some small ice falls off of glaciers on Sunday. The last reported avalanches were wind slab avalanches in alpine terrain on Thursday and Friday, including a small (size 1) skier triggered wind slab near Shames (see this MIN report). Triggering wind slabs remains possible in alpine terrain.

Snowpack Summary

Open terrain is heavily wind affected, while softer snow can be found in sheltered terrain. Warm inversion temperatures have likely left a thin surface crust in the alpine. In steep wind affected terrain wind slabs may still be reactive to human triggering, especially where they sit above sugary faceted snow or feathery surface hoar crystals. Snowpack depths at treeline likely range from 90-160 cm and taper quickly at lower elevations.

Problems

Wind Slabs

An icon showing Wind Slabs

Hard wind slabs exist in alpine terrain and may still be reactive to human triggering.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Dec 10th, 2019 4:00PM