Forecast snowfall amounts for Saturday night vary greatly across the region. If more than 20cm falls in your riding area, the Avalanche Danger in the alpine may be HIGH.
Confidence
Moderate - Forecast snowfall amounts are uncertain on Sunday
Weather Forecast
On Saturday night expect 10-15cm of new snow with another 10cm falling on Sunday. A mix of sun and cloud is forecast for Monday while light snowfall is expected on Tuesday. Winds should be extreme and southwesterly on Sunday, becoming mainly light on Monday and Tuesday. Freezing levels should hover between 1300 and 1500m for the forecast period.
Avalanche Summary
Backcountry observations have been limited due to inclement weather although I suspect there was a widespread round of storm slab avalanche activity in response to recent heavy snowfall and wind.
Snowpack Summary
Heavy snowfall on Friday (up to 50cm in 24 hours) and extreme southerly winds have formed deep and reactive storm slabs on lee and cross-loaded alpine and treeline features. On windward terrain, extensive scouring has been reported. Ongoing stormy weather has also encouraged extensive cornice growth. Recent storm totals (which vary from about 100cm to over 130cm) overlie a temperature crust, old wind slabs and spotty surface hoar. The mid and lower snowpack are 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.
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.