Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
Wednesday: Cloud building by afternoon, with a few flurries possible. Southerly winds increasing by afternoon. Freezing level near valley bottom.Thursday/Friday: A few cm snow each day. Moderate southerly winds. Freezing level rising to 1500m late Thursday.
Avalanche Summary
Solar warming has caused many avalanches on steep sunny aspects, mostly in the size 1-1.5 range. Large chunks of cornice fall have been reported most days, with limited effect on the slope below.
Snowpack Summary
Very warm alpine temperatures recently melted surface snow layers. A crust (or moist snow, depending on the time of day) now exists to ridge top on solar aspects. Large weak cornices are plentiful and wind slabs exist in certain areas. The upper snowpack appears to be settling well. Below about 1500m, crust/facet layers buried in early January are still causing operators concern.
Problems
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.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.