Avalanche Forecast

Issued: Dec 11th, 2022 4:00PM

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

Avalanche Canada zryan, Avalanche Canada

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For the best riding seek out sheltered slopes where the recent storm snow hasn't been wind-affected.

The snowpack is shallow and early-season hazards are abundant, travel carefully!

Summary

Confidence

Moderate

Avalanche Summary

On Saturday, a natural storm slab avalanche was observed on a west aspect at treeline.

Looking forward to Monday, we expect storm slab activity to drop off with cooling temperatures. The avalanche problem will likely be more confined to wind-loaded areas at upper elevations. Be cautious around these wind slabs as they may remain reactive to human triggering.

Keep sharing your observations via the MIN; it helps strengthen our information gathering.

Snowpack Summary

In deeper zones near ridges, the snowpack is around 120 to 170 cm, which is low for early December. Alpine terrain in windy areas is scoured and bare.

Surface: Boot top powder in deep areas. Same old crusts, facets, and rocks on wind-scoured slopes.Upper-pack: In sheltered areas below the fresh snow is well-developed surface hoar. Generally, there's 40 to 70 cm of low-density and faceting (aka weak) snow in the upper pack.Mid-pack: November crust, with a layer of soft facets above. This is the primary weak layer, found pretty much halfway down.Lower-pack: a mixture of old crusts and facets but some suggest that these layers are a bit harder or stronger than what's found in other regions (e.g. Duffy or Hurley).

Weather Summary

Sunday night

Clear periods. Alpine temperatures reach a low of -11 °C. Ridge wind northeast 20 km/h. Freezing level at valley bottom.

Monday

Sunny with cloudy periods. Alpine temperatures reach a high of -7 °C. Ridge wind northeast 15-30 km/h. Freezing level rising to 400 meters.

Tuesday

Cloudy with sunny periods. Alpine temperatures reach a high of -3 °C. Ridge wind north 10 km/h. Freezing level rising to 800 meters.

Wednesday

A mix of sun and cloud. Alpine temperatures reach a high of -2 °C. Ridge wind northeast 15 km/h. Freezing level rising to 800 meters.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Seek out sheltered terrain where new snow hasn't been wind-affected.
  • Stay off recently wind loaded slopes until they have had a chance to stabilize.
  • 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

Watch for pockets of wind slab on the lee side of ridges or ribs. If northerly outflow winds pick up on Monday, fresh wind slabs may form anywhere there is powdery, dry snow available to be transported.

With the sugary, faceted, and weak snowpack wind slabs could step down to the middle of the snowpack, resulting in larger than expected avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Dec 12th, 2022 4:00PM