Regions
South Coast Inland.
Watch for signs of recent wind loading in exposed terrain. Wind slabs are expected to be reactive to human triggering on Wednesday.
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Thursday
Weather Forecast
Lingering flurries are expected on Wednesday morning and sunny breaks are possible in the afternoon. Alpine wind is forecast to be moderate from the west to northwest direction and freezing levels are expected to reach around 800 m. The next storm front is forecast to arrive Wednesday overnight. 10-20cm of new snowfall is forecast by Thursday evening. Alpine wind is forecast to be strong from the southwest and freezing levels are forecast to remain around 800 m. Friday is currently forecast to be dry and sunny.
Avalanche Summary
No new avalanches have been reported from the region in several days. On Wednesday, wind slabs are expected to be the primary concern. Ongoing strong southerly winds are expected to be redistributing the 10-20 cm of new snow from Tuesday.
Snowpack Summary
10-20 cm of new snow has accumulated since Monday. This new snow sits over a variable interface which consists of wind affected surfaces, faceted (sugary) snow, or surface hoar. The surface hoar has been observed up to 5 mm in size in the Duffey Lake area. A thin sun crust may also exist in the upper snowpack and was reported around Coquihalla area over the weekend. Recently strong southerly winds have formed new wind slabs in leeward and cross loaded features in wind exposed terrain. The mid and lower snowpack are generally expected to be well settled and stable.
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.