Unsettled stormy weather will continue through the weekend. Travelers in avalanche terrain will need to have good skills to assess the changing conditions.
Weather Forecast
A continuous series of low pressure systems are expected to move through the area until Monday. With each passing front, expect strong westerly winds, light to moderate precipitation and noticeable rising and falling of the freezing level from the surface to 2200 m. More stable conditions are expected by Tuesday.
Snowpack Summary
Cool overnight temperatures may create a week melt freeze crust at treeline and below treeline that will likely loose strength by mid-day Sunday. Strong NW winds have been building windslab with the 15 to 20 cm of new snow on SE aspects in the alpine.
Avalanche Summary
Poor visibility prevented alpine avalanche observations on Saturday. Several wet slab avalanches to size 1.5 were observed below treeline on steep rocky terrain. These avalanches were triggered by light to moderate rain on a warm snowpack.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Sunday
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.
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.
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.