Recent additional load to the wind slabs and cornices require careful route finding and decision making.
Confidence
Fair - Forecast snowfall amounts are uncertain
Weather Forecast
Saturday will see more precipitation with a possibility of 10 15 cm at upper elevations and rain below 1500m. Sunday should be clear with freezing levels dropping to 1000m then slowly rising as another wave of moisture arrives on the coast. Winds will be light to moderate at ridge tops.
Avalanche Summary
Numerous explosive triggered avalanches to size 1.5 reported yesterday as well as one 1.5 skier accidental on a wind slab. Forecast sunny skies may increase the likelihood of loose wet avalanches on solar aspects, and with recent warm temperatures, cornice failures should be on the "lookout list".
Snowpack Summary
Melt-freeze crusts can be found on solar aspects in the alpine, and on all aspects at lower elevations. On high north-facing terrain, old wind slabs and surface facets still exist. The snowpack is generally strong and well settled. However, be aware that cornices may become weak with daytime warming. and incoming precipitation will develop wind slabs on lee slopes.
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.