Northwest Coastal

Storm slab problems vary by elevation band. Wind loading patterns are your guide to avoiding slabs at higher elevations. Further down, carefully manage steep, sheltered slopes that may harbour surface hoar.

Moderate -

Saturday night: Flurries bringing approximately 5 cm of new snow. Moderate to strong southeast winds.Sunday: Cloudy with continuing scattered flurries bringing 2-4 cm of new snow. Light variable winds. Alpine high temperatures around -7.Monday: Cloudy with flurries bringing 5-10 cm of new snow, continuing overnight. Light to moderate southwest winds. Alpine high temperatures around -7.Tuesday: Mainly cloudy with isolated flurries and a trace of new snow, increasing overnight. Strong southeast winds. Alpine high temperatures of -6.

Reports from Friday included observations of numerous older storm slab releases that occurred during last week's storm. These reached to Size 2.5 and were focused on terrain around a 38 degree incline. Both north and south aspects were active. Another older Size 2.5 persistent slab release was also noted. This slab was about 80 cm thick, failed on a low elevation moraine feature on a north aspect, and is suspected to have run on the weak layer from late December.Reports from Thursday included observations of several storm slabs releasing naturally, remotely (from a distance), and with skier traffic. Avalanche sizes ranged from Size 1-2. The remote release was noted to have slid on lower angle terrain over a surface hoar on crust 'combo' left behind by the recent inversion. Looking forward, the recent storm snow is expected to become generally more stable, except where it overlies pockets of surface hoar and where wind -affected. Surface hoar is more likely to exist in sheltered openings at mid elevations. Wind slabs at ridgecrests and around exposed terrain features are an increasing concern.

Last week's storm brought about 30 cm of new snow to the region. Northern parts of the region saw about half this amount. The new snow buried a mix of old wind slabs and temperature crusts left over from last weekend. More isolated surface hoar has been observed under the new snow at mid elevations that experienced cloud cover during recent inversion conditions. Storm slabs have been particularly reactive where this surface hoar exists.Professionals have been monitoring a few layers in the upper snowpack, including crusts and surface hoar layers buried 40-80 cm below the surface. Although these layers have been reactive in recent snowpack tests, only one recent report exists of a persistent slab releasing over the late December weak layer. The lower snowpack is generally strong, with the exception of areas around Stewart and further north where a basal crust and facets exist.