A steady flow of moisture has gradually accumulated storm snow amounts over the past 2 days.
Confidence
Moderate - Forecast snowfall amounts are uncertain on Monday
Weather Forecast
MONDAY: Periods of snow, accumulations 5-10cm Sunday night and 5-10cm through Monday / Moderate southwest wind / Alpine temperature -2 TUESDAY: Cloudy with scattered flurries / Light to moderate south wind / Alpine temperature -4 WEDNESDAY: Cloudy with scattered flurries / Light southwest wind / Alpine temperature -6
Avalanche Summary
Avalanche activity on Saturday Sunday was reported as thin windslabs in alpine lees to size 1 that were reactive to skier traffic.
Snowpack Summary
20-30cm of new snow sits on a crust that formed on Saturday. This sits above about 20cm of moist snow. The new snow has been redistributed by moderate to strong southeast through southwest winds on Sunday. Up to 100 cm below the surface there is a widespread melt-freeze crust that was buried on December 15th. This layer has not produced much in the way of avalanche activity and is likely trending towards dormancy. Beneath the mid-December crust, the lower snowpack is generally strong and well settled.
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.