Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain for the entire period
Weather Forecast
Synopsis: The precipitation associated with a Pineapple Express weather system approaching the province Friday is not forecast to affect the region. However, the associated warm temperatures and wind will. Friday: Light precipitation, strong gusting to intense westerly winds and alpine temperatures -3. Freezing level to 2200m.Saturday: Light precipitation, moderate to strong west winds, and freezing level of 2200m. Sunday: Light precipitation, light southeast winds, and freezing level of 1800m.
Avalanche Summary
Recent reports indicate a size 2 skier triggered avalanche off of a windloaded ridgeline feature running on a layer of facetted crystals. A subsequent size 1 avalanche was triggered nearby. This was in the Three Sisters area just north of Fernie.
Snowpack Summary
In protected areas up to 30cm of the most recent low density new snow sits on the surface. This has been shifted onto lee slopes by strong west and southwest winds. New storm slabs, cornices and wind slabs are likely. Mid and lower snowpack layers are generally 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.
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.