Rising avalanche danger: Time to reel in your terrain exposure.
Confidence
Low - Due to the number of field observations
Weather Forecast
A series of storms is coming in quick succession over the next few days. Disagreement between weather forecast models is making it hard to pin down specifics, but you can expect snow, south to south-west winds and fluctuating freezing levels, peaking around 1500 m. Snowfall: 10-20 cm on Saturday, 10-15 cm on Sunday, 20-30 cm on Monday. Locally heavier amounts are quite likely. For more details check out https://avalanche.ca/weather.
Avalanche Summary
No new avalanche activity has been reported, but I expect a natural avalanche cycle is already underway in areas with the heaviest new snow and/or wind effect. I would anticipate avalanche sizes to go up through the weekend.
Snowpack Summary
Up to 40 cm recent snow has fallen over a variety of old surfaces including wind-stripped north aspects, hard wind slabs, facets, sun crusts and/or large-sized surface hoar. Of most immediate concern is a crust/surface hoar interface that is already super-reactive. Reports suggest that the surface hoar exists up to about 2000 m and the crust maybe found on all aspects. I wouldn't rule out the possibility of weak interfaces at higher elevations, especially crusts. Strong southerly winds are transporting snow onto lee slopes and creating deep wind slabs. Deeper in the snowpack, surface hoar interfaces that were key players in November seem to be inactive. In the highest and shadiest spots, a crust/facet interface may be found near the ground.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.