Sea To Sky

Avalanche danger is expected to increase over the weekend.

Recent observations are limited to isolated human-triggered Size 1 fresh wind slabs. One was 20m wide by 20cm deep on a NE facing alpine slope.

Fair - Intensity of incoming weather is uncertainfor the entire period

Friday: Light snowfall in the morning with 2-5cm expected. Freezing levels around 1200m and moderate southwesterly winds before precipitation picks up, winds increase and freeing levels rise in the evening. Saturday: Another 20-30cm late in the day is expected to add to the 15-25cm of new snow already on the ground. Freezing levels as high as 1700m and strong westerly winds. Sunday: Continued moderate snowfall and moderate to strong southwesterly winds, with freeing levels back around 1200m.

Alpine areas are wind-hammered with scoured and pressed surfaces, exposed crusts, and pockets of hard and soft wind slabs. Buried surface hoar and/or facets persists 10-20cm below a weak rain crust on sheltered treeline slopes and below. Recent compression tests on a treeline slope produced easy to moderate sudden collapse results down 65cm on on this weakness where it was wind-loaded. Watch this layer as it gets more load and a thick cohesive slab develops, particularly below treeline where the buried surface hoar is especially large. A strong mid pack overlies weak basal facets and depth hoar in shallow alpine areas. This deep persistent weakness may also deserve attention with more load.