Rising freezing levels, heavy precipitation, and strong winds are a recipe for High avalanche danger!
Weather Forecast
A series of powerful storms are going to wallop the coast over the coming days bringing heavy precipitation and strong winds. Unfortunately the freezing level could rise as high as 2000m on Tuesday. However, higher elevations could see snowfall accumulations of between 40 and 60cm. Freezing levels are forecast to fall back to between 1000 and 1500m for the remained of the forecast period with another 55cm expected by Friday. Winds will be moderate from the southwest.
Avalanche Summary
There have been reports of a widespread natural avalanche activity from the Whistler area that is likely indicative of what is going on in the rest of the Sea to Sky region. This cycle is expected to continue as a series of storms pummels the coast range over the next couple of days.
Snowpack Summary
It's been snowing hard above 1500m where deep storm slabs are developing. In addition, extreme southwesterly winds have produced even deeper winds slabs that I expect extend well into lee features both in the alpine and at tree-line. Below tree-line snow depths are still below threshold for avalanches.
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.