Forecasted precipitation quantity vary spatially for the region. This forecast takes into account where most amounts should occur, most likely the S part of the region.
Confidence
Poor - Forecast snowfall amounts are uncertain for the entire period
Weather Forecast
Monday Night and Tuesday: The first of a series of systems approaching the interior is expected to start spreading precipitation over the region early Tuesday. Light to moderate precipitation amounts (around 15 mm water equivalent in areas in the SW part of the region) are expected with strong SW winds. Freezing level will start rising to reach around 1700 m. and will stay high for the rest of the period.Wednesday: Precipitation easing off but still some moisture available. Winds are forecasted to be strong to extreme from the W. Temperatures staying warm and freezing rising near 2000 m.Thursday:Light precipitation is expected with similar freezing levels and lighter winds switching from the SW.
Avalanche Summary
There was report of a size 3 skier remote triggered on an East facing slope in the region. The avalanche is suspected to be a recent windslab sliding on an old surface. Otherwise, no other avalanches were reported.
Snowpack Summary
A trace of new snow overlies a variety of surfaces; hard wind slabs lee of N, SW and W winds in alpine and treeline features, a well developed surface hoar in shaded areas above 1700 m., a melt-freeze crust below that elevation and a 3 cm sun crust on solar aspects at all elevations. The forecasted precipitation and warm temperatures will add a good load to the snowpack (fair bit of uncertainty about quantities, but right now looking like 20 mm in water equivalent until Thursday). I suspect that the variety of surfaces described previously will become gradually more reactive as the load add up starting tomorrow. This could also make the 30 cm deep surface hoar layer that has been reactive to skier traffic (see avalanche observation section) even touchier, creating a potential for even larger avalanches.
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.