The incoming storm will form new wind slabs and increase the avalanche danger at higher elevations.
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Monday
Weather Forecast
SUNDAY: Flurries starting in the evening, moderate southeast winds. Alpine temperatures around -4. MONDAY: 10 cm of new snow by the morning with another 10-15 possible during the day. Moderate to strong southwest winds. Alpine temperatures around -6. TUESDAY: Clearing in the morning, light northeast winds, alpine temperatures around -12 Celcius. WEDNESDAY: Sunny with light northerly winds. Alpine high temperatures near -12 Celcius.
Avalanche Summary
No new avalanches observed.
Snowpack Summary
5-15 cm of snow from Friday covers a variable surface with a mix of soft wind slabs, hard wind slabs, sastrugi, faceted snow, and even some surface hoar. Last week's winds reverse loaded many terrain features and formed stubborn wind slabs on a surprising range of aspects. An interface of faceted (sugary) snow and surface hoar was buried on Boxing Day and can be found up to 100 cm deep. Recent observations suggest the snow has bonded well to this interface. Snowpack layers below this interface are also generally well bonded.
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.