Avalanche Forecast
Issued: Dec 25th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
jpercival,
Avalanche Canada
Carefully assess conditions as you gain elevation. In wind exposed terrain above the freezing line, wind slabs are likely.
Summary
Confidence
Moderate
Avalanche Summary
Over the weekend period and on Christmas day. Explosive avalanche control operations working in the alpine near whistler, trigger two size 2 avalanches and numerous size 1 and size 1.5 wind slab avalanches. They all failed on a buried hard melt-freeze crust from December 20th. A noted cornice release occurred while utilizing explosives, dropping sizable chunks into the track and runout.
Snowpack Summary
A melt-freeze crust in the alpine was buried December 20th and can be found down 30 cm. Expect this layer to become deeper as snowfall and wind continues. This layer has been reactive to explosive testing and in areas that are thinner may be reactive to human triggering.
At treeline and above a layer of note is buried around 70 cm deep. It consist of a crust that tapers at higher elevations, and surface hoar in sheltered areas.
Overall, the snow depth remains shallow, with average treeline snowpack depths between 70 and 100 cm.
Weather Summary
Monday Night
Cloudy. Snow and some rain expected 5 to 25 cm. Freezing level rising to 1200-2000 m. Treeline temperature around 0 °C. Strong, south west ridgetop wind.
Tuesday
Mostly cloudy with afternoon clearing. Snow, expected to cease in the am 1 to 5 cm. Freezing level around 1500 m. Treeline around -1°C. Strong south west ridgetop wind.
Wednesday
Periods of clearing. No new snow expected. Treeline temperature around 0 °C. Freezing level rising to 1700 m. Moderate south ridgetop wind.
Thursday
Cloudy. Snow expected 5 to 15 cm. Treeline temperature around 0 °C. Freezing level 1800 m. Moderate south ridgetop wind.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
Problems
Wind Slabs
Expect wind slabs to be reactive at elevations where a melt-freeze crust is present.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 26th, 2023 4:00PM
