Avalanche Forecast

Issued: Dec 10th, 2022 1:30PM

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

Avalanche Canada JMackenzie, Avalanche Canada

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The snowpack is very sensitive to human-triggering. Forecasters were able to easily remote and skier trigger avalanches failing down 40-50cm at treeline on Friday. Avoid steep, convex and unsupported slopes as the snowpack adjust to this new load.

Summary

Confidence

High

Avalanche Summary

On Friday numerous skier controlled size 1 avalanches were triggered by forecasters. These failures occurred down 40cm on the Nov 25 facet layer.

Snowpack Summary

A few cm's of new snow in the past 24hrs. The winds have been strong in the Alpine with many windward slopes stripped bare to rock, with pockets of hard wind slab on the lee side. There are two main layers of concern found in the snowpack. The Nov 25 facet layer is down 15 to 30cm and the Nov 16 surface hoar is buried 30 to 50cm. Both of these layers are producing whoomphs, cracking and very easy test score in snowpack tests. In addition, the basal layers are fully facetted. Forecasters have very little confidence in the snowpack.

Weather Summary

Sunday should be a mix of sun and cloud with temperatures climbing to -8C by midday. A couple of cm's of snow are expected, with generally light SW winds.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be especially cautious as you transition into wind affected terrain.
  • Avoid convexities, steep unsupported terrain and rocky outcroppings.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
  • Remote triggering is a concern, watch out for adjacent and overhead slopes.
  • Watch for areas of hard wind slab on alpine features.

Problems

Persistent Slabs

An icon showing Persistent Slabs

Where the surface snow is dense enough to form a slab, the Nov 25 and 16 layer are reactive to skier traffic. Remote triggering is possible.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2.5

Wind Slabs

An icon showing Wind Slabs

Wind slabs are found along ridgelines and in gullied terrain. These avalanches will likely step down to the weak base layers.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 11th, 2022 4:00PM