Regions
Northwest Coastal.
Watch for wind slabs lurking in unusual places as the wind shifts direction.
Confidence
Fair - Due to the number of field observations
Weather Forecast
Cold and clear with strong outflowing N-NE winds.
Avalanche Summary
Over the last three days we've had reports of naturally and skier-triggered size 1-2 slabs, mostly wind slabs on lee slopes at treeline and above. Explosive control on Wednesday produced storm slab and wind slabs up to size 2.5.
Snowpack Summary
Up to 30cm new snow from Friday night may have buried old wind slabs. New wind slabs are likely to form on south to west-facing slopes as we shift into an outflow wind pattern. The mid and lower snowpack are generally well-settled. Several old crust layers exist but these appear to be well bonded.
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.