Avalanche Forecast

Issued: Dec 12th, 2023 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 lbaker, Avalanche Canada

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Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

Summary

Confidence

High

Avalanche Summary

On Monday, evidence of the natural avalanche cycle from last weekend continued to be reported with size 1 to 1.5 wind slab and storm slab avalanches being reported.

Explosives control in the region produced size 1.5 storm slab avalanches in lee features above 1900 m.

Thank you to everyone who has been sharing observations on the Mountain Information Network. All the information and photos are very appreciated by forecasters!

Snowpack Summary

A thin melt freeze crust covers 15-20 cm of recent snow. Above 1900 m recent snow overlies a layer of preserved surface hoar above a crust. This weak layer was very reactive during the last storm cycle.

Below 1900m snow surface is moist or in various stages of refreezing. 50 cm down is a thick widespread supportive crust.

Overall, the snow depth remains relatively shallow, with numerous hazards present at or just below the snow surface across all elevations.

Weather Summary

Tuesday Night

Partly cloudy with no precipitation, southwest alpine winds 30 to 50 km/h, treeline temperature 0 °C, freezing levels remain between 2000 and 2500 m overnight.

Wednesday

Cloudy with isolated flurries, 1 to 5 mm accumulation, southwest alpine wind 60 to 80 km/h, treeline temperature -2 °C, freezing levels drop to 1200 m through the day.

Flurries continue overnight bringing another 10 to 20 mm of accumulation.

Thursday

Cloudy with scattered flurries, 2 to 6 mm accumulation, northwest alpine wind 10 to 25 km/h, treeline temperature -3 °C, freezing level 1000 m.

Friday

Mainly cloudy with scattered flurries, 3 to 10 mm accumulation, southwest alpine wind 30 to 50 km/h, treeline temperature -3 °C, freezing level 2000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong southwest winds are redistributing available snow into fresh wind slabs in alpine lees. Use caution trastioning into lee terrain.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 13th, 2023 4:00PM