Pack your assessment mindset to check out the new snow situation on Sunday and be ready to dial back your terrain choices if you encounter signs of instability.
Steep, wind-loaded features will be the most likely to trigger in the wake of Saturday's storm. It will take some time for the new snow to form a reliable bond with the previous surface.
Strong sunshine will destabilize snow on south-facing slopes on Sunday. This problem will likely be limited to new snow accumulations.
Early reports from Saturday's storm in the Whistler area showed ski cutting and explosives producing size 1 releases in ridgetop lees in the morning, with snow and wind ongoing.
No reports yet from the Duffey, but slabs formed at higher elevations, especially where wind loaded, will remain a concern for Sunday.
On Friday, explosives control in the Duffey produced one size 1.5 avalanche that failed on basal facets in an area of very shallow snowpack.
Saturday's storm should leave us with 15 to 30 cm of windblown new snow above treeline, tapering to a rain-soaked surface below about 1500 m.
Where new snow accumulated, it mainly buried a widespread crust, mostly thin but more supportive on sun-exposed slopes. It may add to heavily wind-affected dry snow on north-facing slopes above 2200 m.
Below the evolving surface, the thick late-January crust sits under about 40 cm of old snow. This snow is moist below 2000 m but may contain facets on higher north aspects.
The mid to lower snowpack is generally well settled and strong. Snowpack depth ranges from 150 to 250 cm at treeline elevations.
Saturday Night
Becoming mostly clear after the storm finishes with 5 to 10 cm of new snow. 20 - 50 km/h southwest ridgetop wind, easing. Treeline temperature falling to -6 °C.
Sunday
Sunny. 20 to 30 km/h southwest ridgetop wind. Treeline temperature falling to -6 °C. Freezing level 1400 m
Monday
Becoming mostly cloudy with isolated flurries. 30 to 40 km/h southwest ridgetop wind, increasing. Treeline temperature -6 °C. Freezing level 1200 m.
Tuesday
Mostly cloudy with isolated flurries. 20 to 40 km/h southwest ridgetop wind, easing. Treeline temperature -6 °C. Freezing level 1300 m.
More details can be found in the Mountain Weather Forecast.
