Solar radiation will cause surface layers to become more reactive. Lower elevation snowpack will become isothermal.
Weather Forecast
Cloudy with sunny periods and moderate S winds. Alpine temps of -2C and a freezing level of 1900m. Thursday brings scattered flurries and 5cm of snow to the alpine along with mod west wind and 1800m freezing level.
Snowpack Summary
25cm new snow in the last 48hrs with freezing levels dipping to around 1000m last night. Moist surface snow on all aspects the last couple of days with numerous moist slides in the highway corridor. Expect windslabs on lee features from earlier SW wind. Cornices failing sporadically with some triggering large avalanches. Isothermal snow below TL.
Avalanche Summary
9 moist avalanches to size 2.5 recorded in the highway corridor yesterday. Two days ago a field team reported touchy surface wind slabs on northerly lee aspects at 2200m. The 10-15cm soft slabs were easily failing with ski cuts and sliding on a temperature crust.
Confidence
Timing or intensity of solar radiation is uncertain
Problems
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.
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.