Avalanche Forecast
Issued: Dec 4th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
mconlan,
Avalanche Canada
Travel in avalanche terrain is not recommended as an intense storm loads a weak snowpack. A natural avalanche cycle is likely to occur.
Summary
Confidence
High
Avalanche Summary
Many storm and wind slabs released on Sunday within the snow that overlies the weak layer of surface hoar described in the Snowpack Summary. The avalanches were generally small to large (size 1 to 2) and triggered by riders and explosives at treeline and alpine elevations.
Looking forward, natural and human-triggered avalanches are very likely as an intense storm impacts the region.
Snowpack Summary
An intense and warm storm will rapidly load the snowpack with new snow and rain. A weak and feathery surface hoar layer buried about 20 to 30 cm will rapidly destabilize with the added load. This layer may be associated with a hard melt-freeze crust.
The remainder of the snowpack is weak and faceted. Snowpack depths are approximately 60 to 80 cm at treeline, which rapidly tapers with elevation below treeline.
Weather Summary
Monday Night
Cloudy with snow switching to rain below approximately 2500 m, accumulation 5 to 15 cm of snow possible at the highest elevations. Southwest alpine wind 40 km/h. Treeline temperature 0 °C. Freezing level rising from 1300 m to 2500 m.
Tuesday
Cloudy with rain or snow, 20 to 40 cm snow accumulation possible above the rain-snow line near 2100 m. Southwest alpine wind 20 to 40 km/h. Treeline temperature 2 °C. Freezing level 2500 m.
Wednesday
Cloudy with rain or snow, 10 to 20 cm snow accumulation possible above the rain-snow line near 2000 m. Southwest alpine wind 20 to 40 km/h. Treeline temperature 1 °C. Freezing level 2200 m.
Thursday
Cloudy with rain switching to snow, 20 to 50 cm snow accumulation possible above the rain-snow line near 1500 m. Southwest alpine wind 20 to 40 km/h. Treeline temperature 0 °C. Freezing level 2000 m dropping to 1300 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid avalanche terrain during periods of heavy rain.
- Be aware of the potential for larger than expected storm slabs due to the presence of buried surface hoar.
- If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
- 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
Storm Slabs
Snow and rain will rapidly load a buried weak layer, likely forming natural avalanches. The most likely terrain features to release are where the snowpack is sufficiently deep and smooth.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Loose wet avalanches are likely wherever rain soaks the snowpack.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 5th, 2023 4:00PM
