Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Regions
South Coast.
Maintain elevated caution around areas where wind loading has occurred. Small avalanches can have big consequences around cliffs and other terrain traps.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
Tuesday: Cloudy with flurries beginning late in the day and bringing 10-15 cm of new snow by Wednesday morning. Moderate to strong southwest winds. Freezing level dropping to 500 metres as the temperature inversion breaks down. Alpine high temperatures of -4.Wednesday: A mix of sun and cloud. Light north winds. Freezing level to 700 metres with alpine high temperatures of -2.Thursday: Mainly cloudy with flurries increasing over the day and bringing approximately 15 cm of new snow by Friday morning. Light southwest winds increasing over the day and overnight. Freezing level to 600 metres with alpine temperatures of -3.
Avalanche Summary
On Saturday, a cornice collapse was the likely cause of a size 2 avalanche on a north facing slope near the West Lion. See here for images and more details. Pockets of thin wind slab may exist in wind-loaded areas in the high alpine and may be sensitive to human triggers.
Snowpack Summary
Rain at the end of the week saturated snow surfaces and only higher alpine elevations were lucky enough to receive a light cover of new snow. With the arrival of cold temperatures, the upper snowpack has locked up as a firm crust. Where new snow exists above the crust, it has been redistributed by recent strong southwest winds. The average snowpack depth at treeline is 300 cm of well settled snow with no significant layers of concern.
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.