Avoid travelling on or under any slopes getting the heat of the sun.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Thursday is expected to be cloudy and dry, with light southerly winds and the freezing level around 1800 m. On Friday, light snow begins in the afternoon, becoming moderate overnight and easing on Saturday (15-25 cm total). The freezing level is expected to fall towards 1400 m with this snow. Winds are light to moderate from the S-SW.
Avalanche Summary
Explosives-triggered cornice fall produced some large (size 2-3) avalanches yesterday. A few wind slabs were also triggered by skiers and naturally. In some areas affected by the sun, loose wet avalanches were observed.
Snowpack Summary
Cornices are large and weak. Recently formed storm slabs and wind slabs are generally settling, but may still be reactive to human triggers in specific terrain, and may be triggered by cornice fall. Slopes that receive direct sun are likely to develop a sun crust overnight and become moist and weak by day. Several crusts can be found in the upper metre of the snowpack. A layer of surface hoar buried in early January is down 1-2 m. In most places it is thought to be capped by a thick strong crust. It is becoming increasingly hard to make this layer fail in snowpack tests and triggering an avalanche on it is unlikely.
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.
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.
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.