Wind could be the initial driver of avalanche danger as the storm gets started Saturday. Let the blustery weather guide you to sheltered areas less prone to slab formation.
Recent snow and wind have formed wind slabs near ridge crests. New snow and elevated southwest wind should drive an increase in slab formation on Saturday.
New snow has been adding to the load over weak layers from early February. Surface avalanches may have potential to step down to this layer to create a larger, more destructive avalanche.
Wednesday's reports showed 5-10 cm in the Whistler area yielding small slab and dry loose results with ski cuts and explosives. Slabs were more restricted to north aspects.
Thursday's reports were a bit quieter with generally small wet loose and dry loose releases punctuated by small ski cut slabs running on crust in north-facing terrain.
Last week had a more sporadic pattern of wind slabs triggered on buried persistent weak layers of facets, a problem that remains in play.
10 cm of new snow should accumulate in the region by end of day Saturday. It will likely bury new sun crust on solar aspects but otherwise add to 10-20 cm of recent snow settling over a mix of crust on south aspects and lower elevations, faceted snow and/or small surface hoar in sheltered terrain, and wind-affected snow in the open. Areas where wind loading has increased the depth of new snow and where larger preserved surface hoar is buried are the most concerning.
30 to 40 cm of snow sits above an older layer of faceted snow or more isolated surface hoar at treeline and above. Just below it, a widespread, thick crust is about 30 to 60 cm deep. This problematic combination remains a concern as load increases above it.
Friday night
Cloudy with flurries bringing about 5 cm of new snow. 30 to 40 km/h southwest alpine wind. Freezing level falling to 1000 m.
Saturday
Cloudy with continuing flurries bringing about 5 cm of new snow. 30 to 40 km/h southwest alpine wind. Treeline temperature -3 °C with freezing level to 1200 m.
Sunday
Cloudy with moderate to heavy snowfall bringing 20 - 30 cm of new snow, including overnight amounts. 35-65 km/h southwest alpine winds, increasing. Treeline temperature -4 with freezing level to 1200 m.
Monday
Mostly cloudy with scattered flurries bringing up to 5 cm of new snow, including overnight amounts. 25 - 45 km/h west alpine wind. Treeline temperature -5 °C with freezing level falling to 500 m.
More details can be found in the Mountain Weather Forecast.
