Avalanche Forecast

Issued: Feb 10th, 2020 4:00PM

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

Avalanche Canada jfloyer, Avalanche Canada

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Generally favourable avalanche conditions but watch for wind slabs on steep, wind-affected slopes.

Summary

Confidence

Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.

Weather Forecast

Monday night: Dry with moderate northwesterly winds.

Tuesday: Flurries. Strong northwesterly winds in the morning, decreasing to moderate in the afternoon. Freezing level around 1000 m.

Wednesday: Dry with some sunny breaks. Light southwesterly winds. Freezing level around 1000 m.

Thursday: 10-15 cm new snow. Moderate southwesterly winds. Freezing level around 900 m.

Avalanche Summary

A very large (size 3.5) avalanche was observed on Sunday (although is most likely to have occurred on Saturday) near Whistler on a steep north face at 2400 m. It is suspected to have failed on a layer of facets on a crust from late November. This very large event demonstrates the ongoing need for caution in aggressive alpine terrain.

Other observations on Sunday were limited to small wind slabs on north and east aspect slopes in alpine terrain.

Snowpack Summary

Extreme southerly wind during the last storm has shifted to northwesterly and created wind slabs on northerly, easterly and southerly aspects. The snow surface is heavily wind affected at treeline and in the alpine. The recent storm snow sits on a rain crust below 2000 m. It is uncertain how well the snow bonds to the crust. 

Weak faceted grains and crusts near the base of the snowpack have not been an active avalanche problem recently, despite significant new snow loads. They are still on our radar, especially in inland parts of the region.

Terrain and Travel

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Be especially cautious as you transition into wind affected terrain.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent wind slabs have been reported on north-, east- and south-facing slopes mostly in alpine terrain.

Aspects: North, North East, East, South East, South, South West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

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