Sea To Sky

Storm slabs will become more dangerous and reactive as the new snow piles up.

Choose conservative terrain and avoid wind loaded areas.

High

• We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

On Thursday, near Sky Pilot there was a large (size 2) remotely triggered wind slab from an east facing slope, report here. There were also several small skier-controlled wind slabs in other parts of the forecast area.

On Wednesday, there were a few small slabs triggered with explosives near Whistler.

30 to 40 cm of storm snow is expected by the end of day on Saturday.

This falls on old snow that has been affected by strong to extreme wind. In some sheltered areas, there is a layer of surface hoar underneath that was buried on Monday. It may become more reactive with new load.

The mid-December crust is 100 to 200 cm deep and up to around 2200 m. It's well-bonded to the snow above. Above 2200 m, a layer of facets and a crust from November is at the base of the snowpack. These layers are not currently a concern.

Friday Night
Mostly cloudy. Up to 5 cm of snow. 40 km/h south ridgetop wind. Treeline temperature -3 °C. Freezing level 1200 m.

Saturday
Cloudy. 25 to 35 cm of snow. 40 km/h south ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.

Sunday
Cloudy. 20 to 50 cm of snow. 40 km/h southwest ridgetop wind. Treeline temperature -1 °C. Freezing level 1400 m.

Monday
Cloudy. 50 to 85 mm of snow, then rain. Freezing level 1800 m. 40 km/h southwest ridgetop wind. Treeline temperature 0 °C.

More details can be found in the Mountain Weather Forecast.

• Storm slab size and sensitivity to triggering will likely increase through the day.
• As the storm slab problem worsens, the easy solution is to choose more conservative terrain.
• Make conservative terrain choices and avoid overhead hazard.