Confidence
Fair - Due to the number of field observations
Weather Forecast
The ridge of high pressure will be replaced with a low pressure system on Thursday. The low will hit the North Coast early Thursday and should reach the South Coast by late Thursday. A weak ridge will build behind this system on Saturday.Thursday: Clear in the morning with increasing cloud cover in the afternoon, light precipitation in the evening, freezing levels at valley bottom, winds becoming light westerly in the afternoon.Friday: Light snowfall, freezing levels near valley bottom, light westerly winds.Saturday: Cloudy in the morning, clearing as the ridge builds, freezing levels around 500m, light NW winds
Avalanche Summary
No new avalanches reported.
Snowpack Summary
Recent strong westerly winds have created pockets of touchy wind slab in exposed lee terrain and cross-loaded features, and scoured windward slopes. Roughly 20-30cm of settling storm snow overlies a variety of old surfaces which formed during the early December cold snap. These surfaces include sugary faceted snow (which may overlie a crust in some areas), spotty surface hoar in sheltered terrain, and hard wind slab on south-facing alpine terrain. Snowpack depths vary greatly across the region, but are significantly lower than average for this time of year. Terrain below treeline is still mostly below threshold for avalanche activity. Early season riding hazards such as rocks, stumps and logs are lurking below the surface at treeline elevations. In glaciated terrain the forecast snow might just be enough to hide open crevasses where supportive snow bridges have not yet developed.
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.