South Coast Inland

Watch for residual wind slabs that may be sensitive to human triggers. With a high degree of uncertainty around deep layers in a complex snowpack, this may not be the time to dive into ultra committing lines.

Saturday night: Flurries, trace, moderate to strong southwest wind, freezing level 800 m.

Sunday: Flurries, trace, moderate northwest wind, freezing level 1000 m.

Monday: Sunny, light northwest ridgetop wind, freezing level 1000 m.

Tuesday: Mix of sun and cloud, southwest ridgetop wind building to strong, freezing level 800 m.

Natural cornice falls up to size 2 have been observed recently. Explosive control work on Friday produced wind slab avalanches up to size 2. 

A widespread natural avalanche cycle size 2-3 occurred throughout the region on Wednesday. Avalanche character was predominantly storm slab in the snowy north of the region and wet loose or glide slab in the rainy south. Northwest of Pemberton, several stepped down to buried weak layers resulting in very large (size 3-4) persistent slab avalanches.

• In the south of the region, fluctuating freezing levels during the last storm have resulted in a crust to ridgecrest. At upper elevations, 5-10 cm of dry snow has been blown around by the wind, exposing the crust in some areas and building wind slabs ontop of it in others. This MIN report from Nak Peak on Thursday depicts snow conditions changing with elevation.

• In the north, variable wind effect in the alpine includes scoured windward aspects, sastrugi, hard slab, wind pressed surfaces over lower density snow and isolated pockets of soft snow in sheltered areas. Wind slabs may remain sensitive where they overlie a spotty layer of surface hoar in sheltered terrain or a crust on solar aspects. A widespread surface crust exists below 1600 m.
• A melt-freeze crust from early December is found around 200 cm deep in the snowpack. This crust may have sugary faceted grains sitting above it. This persistent weak layer is most prevalent in the North, northwest of Pemberton where large avalanches have failed on this interface recently. This interface doesn’t seem to be a concern in the South (Coquihalla) and little information is known for the North Cascades or far South in Manning Park.

• Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
• Pay attention to cornices and give them a wide berth when traveling on or below ridges.
• Be aware of the potential for large avalanches due to the presence of buried weak layers.
• When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.