Confidence
Fair - Forecast snowfall amounts are uncertain on Monday
Weather Forecast
The next pulse of moisture looks like it will bring heavier precipitation. Expect about 30-40 cm of snow combined with strong southwest winds on Sunday night. Snow should taper off by Monday morning with a chance of convective flurries Monday afternoon. The freezing level should drop down to valley bottom by Monday as the wind clocks to the northwest. Tuesday morning should be dry and cool with valley temperatures dropping down to about -10.0 and light northwest winds. Cloudy skies with moderate northwest winds are forecast for Wednesday. The freezing level should rise to about 1200 metres.
Avalanche Summary
Some small size 1.0 avalanches were reported that released in thin windslabs on NE aspects.
Snowpack Summary
Forecast strong westerly winds and new snow are expected to build windslabs and a storm slab by Monday morning. East winds during the day on Sunday have reverse loaded some alpine features. There is a mix of wind scoured surfaces and thin stiff windslabs. Reports of a preserved stellar layer exist down 20-40 cm. This layer has been reactive to rider triggers and should remain on your radar. Up to 60cm sits over a variety of old surfaces. These include melt-freeze crusts at lower elevations, old sun crusts on Southerly aspects into alpine elevations and spotty areas of surface hoar in sheltered treeline areas. The mid and lower snowpack is well bonded and strong.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.
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.