Avalanche danger ratings in the south of the region may be higher than posted as heavy snowfall is expected in this area.
Confidence
Fair - Forecast snowfall amounts are uncertain on Monday
Weather Forecast
Sunday night and Monday morning: Moderate snowfall with heavy amounts possible closer to Squamish and in direct coastal areas, easing by mid-day on Monday / Moderate southwest winds with extreme gusts / Freezing level at 1300mTuesday: Mostly clear skies / Light winds / 700mWednesday: Increased cloud / Light winds / Freezing level at 1000m
Avalanche Summary
No new avalanches were reported at the time of publishing on Sunday. I would expect that to change with snow and wind forecast for the area on Sunday night.
Snowpack Summary
Recent snow and strong southerly winds have created pockets of touchy wind slab in exposed lee terrain and cross-loaded features, and scoured windward slopes. Roughly 20-30cm of settling storm snow overlies a variety of old surfaces which formed during the early December cold snap. These surfaces include sugary faceted snow (which may overlie a crust in some areas), spotty surface hoar in sheltered terrain, and hard wind slab on south-facing alpine terrain. The storm snow generally appears to be well bonded to this interface but instabilities may exist in isolated areas.Snowpack depths vary greatly across the region, but are significantly lower than average for this time of year. Terrain below treeline is still mostly below threshold for avalanche activity. Early season riding hazards such as rocks, stumps and logs are lurking below the surface in many areas. In glaciated terrain new snow on the surface might be just enough to hide open crevasses where supportive snow bridges have not yet developed.
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.