Keep decision making conservative in the wake of the storm. New snow is expected to remain reactive to human triggers.
A weak layer of facets above a crust persists in the snowpack in isolated areas like shallow north facing alpine slopes. Storm slab avalanches may step down to this layer resulting in very large, destructive avalanches.
Storm slabs will be most reactive in wind affected features, especially where new snow sits over a crust.
Observations remain limited however, natural avalanche activity is expected to continue with more wind and snow.
Storm totals will vary from 50 cm to over 1 m in the west by Thursday afternoon. Storm snow continues to build over a widespread crust in most areas, except northern areas where storm snow will fall on heavily wind-affected snow.
The mid and lower snowpack is generally well consolidated. A layer of facets exists between two crusts in the mid snowpack, we are uncertain how this layer will react to new storm snow. This layer is most likely triggered by large loads such as step down avalanches.
Below treeline areas have now received enough snow to produce avalanches. Watch for 'early' season hazard of stumps, creeks and rocks.
Wednesday Night
Snowfall rates ease with 10-20 cm expected in western areas. 30-50 km/h southwest ridgetop wind. Freezing levels drop to 500 m.
Thursday
Mostly cloudy. 10-20 cm of snow. 20-40 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 800 m.
Friday
A mix of sun and cloud. 5-20 cm of snow. 20-40 km/h southerly ridgetop wind. Treeline temperature -4 °C. Freezing level 600 m.
Saturday
A mix of sun and cloud. Isolated flurries possible. 20-40 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 800 m.
More details can be found in the Mountain Weather Forecast.
