Confidence
Fair - Due to limited field observations
Weather Forecast
A weak system is expected to enter the south coast on saturday bringing trace amounts of snow. A ridge is anticipated for sunday and monday delivering mostly clear skies.Light westerly winds and freezing levels at or around valley bottom are expected for the forecast period.
Avalanche Summary
One size 2 slab was observed last Sunday on a north facing slope close to Keith's Hut in the Duffey Lake area. It appeared to be skier-triggered from that weekend.No recent avalanche activity has been reported.
Snowpack Summary
5cm of snow fell in the Coquihalla a few nights ago and has buried a thick layer of surface hoar on most sheltered and shady slopes, but no new snow further north means it's still on the surface. This surface hoar may be sitting on a crust in sun and wind exposed areas making it especially touchy as soon as a sufficiently deep and cohesive slab forms. The thick rain crust from last weekend extends up to 1800m and is buried by 10-15cm of faceted snow. Snow pack depths and surface condition are highly variable in wind-exposed areas. Surface hoar buried 70 cms below the surface has been gaining strength, and just off the ground facets have been doing the same.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.