Saturday's storm is expected to pack a bit of a punch in the alpine with a combo of substantial new snow amounts, strong winds, and rising freezing levels. Slabs that form as a result are unlikely to bond well to the current snow surface.
New snow forecast for Saturday is not expected to form a solid bond with the existing snow surface. Expect avalanche danger to increase over the day as new snow is blown into touchy new wind slabs in alpine areas.
Friday night: Cloudy with flurries bringing 5-10 cm of new snow. Light rain below about 1300 metres. Strong southwest winds.
Saturday: Cloudy with a second storm pulse bringing 15-20 cm of new snow. Light to moderate southwest winds. Alpine high temperatures rising from around -3 to 0 with freezing levels rising from 1000 to 1700 metres over the day.
Sunday: A mix of sun and cloud with isolated flurries and a trace of new snow. Moderate west winds. Alpine high temperatures around -6.
Monday: A mix of sun and cloud. Light to moderate west winds. Alpine high temperatures around -8.
For this weekend, the focus is on new snow accumulating above the current snow surface. This new snow is expected to shed easily once sufficient depths accumulate to form new slabs. Strong winds are expected to accelerate both accumulation and slab formation.
Observations in the region are limited, but we have indications that for most areas where snow cover exists, the snowpack is capped by a supportive melt-freeze crust. Above 1800 metres a light, patchy cover of windblown snow can be found in lee areas and small windloaded pockets.
New snow forecast for Saturday is not expected to bond well to either of these surfaces.
Total snow depths of 30-40 cm have been reported at alpine elevations in the Smithers area, with depths diminishing rapidly with elevation below 1500 metres.
