Avalanche Forecast

Issued: Dec 11th, 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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Use caution in wind-loaded areas in the alpine where snow remains dry and wind slabs linger.

Summary

Confidence

Moderate

Avalanche Summary

On Sunday explosives control in the region produced numerous storm slab avalanches up to size 2.

On Saturday, storm slabs were reactive to skier triggering with several, size 1 to 1.5 avalanches being reported. Storm snow was particularly reactive in wind loaded ridgetop terrain.

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

15-20 cm of recent snow and strong southerly winds have built pockets of cohesive slab in the alpine. This overlies a melt freeze crust and in sheltered areas a layer of weak surface hoar.

Below 1900m snow surface is moist. 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

Monday Night

Clear skies with no precipitation, northwest alpine winds 15 km/h, treeline temperature 0 °C, freezing levels 1700 m.

Tuesday

Mainly sunny with no precipitation, southwest alpine winds 30 to 40 km/h, treeline temperature +1 °C, freezing levels rise to 2200 m by afternoon.

Wednesday

Cloudy with flurries, 5 to 15 mm accumulation, southwest alpine wind 60 to 80 km/h, treeline temperature -2 °C, freezing level 1200 m.

Flurries continue overnight bringing another 10 to 15 mm of accumulation.

Thursday

Mainly cloudy with isolated flurries, trace accumulation, northwest alpine wind 15 to 30 km/h, treeline temperature -4 °C, freezing level 800 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.
  • A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
  • 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

Use caution in wind loaded alpine lees where snow remains dry and deep pockets of cohesive slab remain possible to human trigger. Watch for signs of instability as above 0 °C temperatures reach into the alpine.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 12th, 2023 4:00PM