Sea To Sky

Recent storms have set up great skiing for the holiday weekend, but don't overlook the wind slab problem that still exists at upper elevations.

Moderate - Intensity of incoming weather systems is uncertain

Saturday: Mix of sun and cloud with no new snow. Winds light from the northeast. Freezing level to 400 metres with alpine temperatures to -9.Sunday: A mix of sun and cloud with a trace of new snow. Winds light from the west. Freezing level to 200 metres with alpine temperatures to -9.Monday: Heavy snowfall delivering up to 30cm of new snow. Winds strong from the southwest. Freezing level rising to 700 metres with alpine temperatures to -6.

Recent reports include both skier-triggered and natural size 1 avalanches from isolated start zones and convex features. Reports from Wednesday in the region show explosives triggering wind slabs up to size 1.5 in the alpine.

A light snowfall from Thursday deposited 5-10cm of new snow on the surface. Strong winds overnight caused redistribution of this snow in high elevation and wind exposed areas. Where it hasn't blown away, the new snow lies above a variety of hard surfaces that may include sastrugi, wind crust and hard wind slab. Strong to extreme winds formed this surface and caused significant wind redistribution of the underlying storm snow from earlier this week. This 30-50cm of storm snow overlies a variable snow surface from last week that includes either weak faceted snow or surface hoar in sheltered areas at treeline and below. The widespread mid-November crust is buried 1-2m deep in the snowpack. Recent snowpack and explosive tests have shown the crust to be unreactive, but it could remain a problem in shallow alpine start zones.