Watch for the sun coming out on Friday affecting steep sun exposed slopes at all elevations.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain on Friday
Weather Forecast
FRIDAY: Cloudy with sunny periods / Light to moderate southwest wind / Alpine temperature -1 / Freezing level 1500mSATURDAY: Cloudy with sunny periods / Light to moderate west southwest wind / Alpine temperature -2 / Freezing level 1500mSUNDAY: Mix of sun and cloud / Light west wind / Alpine temperature 0 / Freezing level 1700m
Avalanche Summary
Reports on Thursday indicate numerous skier controlled and natural loose wet avalanches to size 1.5 on all aspects up to 2000m. Additionally explosive controlled moist storm slab avalanches were reported to size 2, 20-30cm deep on north and east aspects above 2000m.
Snowpack Summary
Up to 20cm of new snow fell at upper elevations Wednesday night. Thursday during the day the precipitation fell as rain up to 2000m making the snow surface moist or wet. This adds to moist new snow from the previous weekend and all sits on a well developed crust layer that formed up to 1400m on all aspects except south where it formed up to 1700m. The snowpack is generally well settled and continues to transition into a spring melt/freeze regime. Below 1300m the snowpack may be moist or wet through its entire thickness. In the alpine cornices continue to grow large and ever more overhanging.
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.
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.