Regions
Northwest Coastal.
Weather Forecast
A ridge of high pressure is expected to keep the northwest ranges mainly sunny and dry with light winds throughout the forecast period. Freezing levels are expected to reach 1000m on Thursday afternoon, but Friday and Saturday should be colder with 500m freezing levels.
Avalanche Summary
Reports from Tuesday include evidence of a widespread natural cycle to Size 3 primarily due to wind-loading during Monday's storm. On Tuesday afternoon, sun-exposure caused numerous wet loose avalanches up to Size 2.0 involving the recent storm snow running on a sun crust. Large glide avalanche activity also continued on solar aspects.
Snowpack Summary
15-40cm of new snow is generally bonding well to the previous predominately crusty snow surface. However, sheltered shady slopes may be harbouring buried surface hoar and/or preserved old storm snow from last week, which isn't as stable. Furthermore, not only will daytime warming and sun-exposure cause surface snow to lose cohesion, they will also increase settlement rates and decrease slab stability.
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.