Avalanche Forecast

Issued: Jan 10th, 2020 4:00PM

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

Avalanche Canada cgarritty, Avalanche Canada

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Strong winds have taken the spotlight in the wake of the storm. Reports highlight various aspects, so identifying local wind patterns will be key on Saturday. Seek out sheltered low density snow for the best and safest skiing and riding.

Summary

Confidence

High -

Weather Forecast

Friday night: Cloudy with a short flurry bringing a final trace to 5 cm of new snow. Winds shifting to light northwest.

Saturday: A mix of sun and cloud. Light northwest winds. Alpine high temperatures around -15.

Sunday: Mainly sunny. Moderate northeast winds, becoming strong at ridgetop. Alpine high temperatures around -24.

Monday: Sunny. Light to moderate northeast winds. Alpine high temperatures around -25.

Avalanche Summary

Active avalanche conditions existed throughout the region on Friday. Rapid loading from snowfall and wind resulted in widespread natural avalanche activity focused toward higher elevations exposed to strong winds.

Looking forward, new snow from Friday's storm will remain our primary concern. Under forecast cool temperatures sheltered snow may continue to react to human triggers as dry loose sluffs. Greater danger should be expected in areas where winds have created deeper and more reactive slabs. 

Snowpack Summary

Up to 40 cm of new snow is expected to accumulate in the region by the end of the day on Friday, with the deepest accumulations focused near the coast. The new snow has mainly buried wind-affected surfaces at alpine and upper treeline elevations. It may cover a new layer of surface hoar at lower elevations and in sheltered areas or a thin sun crust on steeper south-facing slopes.

Below the new snow interface, 80-100 cm of recent storm snow, also wind affected, has been forming a strengthening bond with an underlying crust up to treeline and yet another array of wind affected surfaces at higher elevations.

Below these layers the snowpack is generally well consolidated. Two older layers of surface hoar are now buried 130-180 cm deep. The recent widespread natural storm slab avalanche cycle was a good test of these layers, and there have been no reports of avalanches stepping down to them.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Keep your guard up at lower elevations. Wind slab formation has been extensive.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent strong and variable winds have been redistributing storm snow into touchier wind slabs at all elevations and on most aspects. Some of the most recent slab formation has resulted from easterly outflow winds.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 11th, 2020 5:00PM