South Coast Inland

Wind slabs are still lingering on many slope aspects at upper elevations. Analyze each slope for signs of wind loading and likely trigger points as you travel.

High -

Friday: Mainly cloudy with isolated flurries bringing a trace of new snow. Winds light gusting to strong from the southwest. Freezing level around 500 metres with alpine temperatures to -9 in the north of the region, -4 in the south.Saturday: Cloudy with sunny periods and no new snow. Winds light to moderate from the east. Freezing level dropping to valley bottom with alpine temperatures around -9 in the north of the region, -6 in the south.Sunday: A mix of sun and cloud with isolated flurries and a trace of new snow in the north of the region, up to 6cm in the south. Winds light from the east. Possible temperature inversion bringing alpine temperatures to -4.

Explosives control in the Duffey Lake area continued to produce Size 1 results in pockets of wind slab on Wednesday. One slide amplified to Size 2.5 due to significant entrainment of snow in the track. Tuesdays MIN report of an avalanche involvement in the Duffey Lake area remains notable for illustrating the heightened consequences of triggering hard wind slab from below the fracture line. No new natural avalanches have been reported, but challenging riding conditions have certainly been keeping some observers from getting out into the mountains.

Recent strong winds and cold temperatures have left our snow surface a mix of soft wind slab, hard wind slab, sastrugi, faceted snow, and even some surface hoar. 60-90 cm of storm snow lies below this surface, the product of last weeks series of storms. Wind slabs are the primary weakness of concern in our current snowpack. As a product of northerly winds, these wind slabs reverse loaded into the terrain in our region, forming mainly on southerly slopes in wind-exposed areas. While recent faceting has actually had the effect of breaking down the cohesiveness of some wind slabs, snowpack tests were producing easy results with occasionally sudden fracture character on wind slab interfaces as recently as Tuesday. For low snow areas such as the Chilcotins, two other layers of concern exist. One is the surface hoar and faceted snow from mid-December buried approximately 50 cm deep. Below this, the 90-125 cm-deep November 12 crust exists. Snowpack tests continue to indicate these could both be viable failure planes in shallow snowpack areas. Elsewhere, these layers are typically much deeper and are generally considered to be stable.