More snow and wind arriving Wednesday means avalanche danger will be High. Persistent slab avalanches are primed for rider triggering.
A weak layer of faceted grains above a melt-freeze crust buried 60 to 120 cm deep is a recipe for large, high-consequence avalanches. This snowpack setup will take some time to strengthen.
Storm slabs remain reactive to human traffic. The slabs are particularly touchy where they sit on weak layers of facets or surface hoar. Expect deeper and touchier slabs in lee terrain features near ridges.
Numerous natural and rider triggered storm slab and persistent slab avalanches size 1 to 3 have been reported the past few days in the alpine and treeline elevation bands. One rider triggered persistent slab avalanches resulted in a full burial/recovery east of Revelstoke. Persistent slabs were mostly on north to west aspects and 60 to 100 cm deep. Some of these avalanches were remotely triggered (from a distance).
Expect persistent slab avalanche activity to continue.
60 to 90 cm of recent snow sits on a variety of layers that it may not bond well to, including surface hoar in wind-sheltered terrain, weak facets, or a hard melt-freeze crust on sun-exposed south and west-facing slopes. The wind has likely formed thicker deposits in lee terrain features near ridges.
A thick and hard widespread crust that formed in early February is buried 60 to 120 cm deep and is found up to around 2400 m. This crust may have a layer of facets above it, which makes it a troublesome avalanche layer.
The remainder of the snowpack is settled.
Tuesday Night
Cloudy with 5-10 cm of snow. 20 to 50 km/h southwest ridgetop wind. Treeline temperature -10 °C.
Wednesday
Cloudy with 10 to 20 cm of snow. 30 to 60 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1500 m.
Thursday
Cloudy with 15 to 30 cm of snow. 30 to 60 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1400 m.
Friday
Mostly cloudy with 3 to 5 cm of snow. 15 to 40 km/h southwest ridgetop wind. Treeline temperature -5 °C. Freezing level 1000 m.
More details can be found in the Mountain Weather Forecast.
