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 because of inclement weather, but I suspect there was a round of storm slab activity in response to new snow and wind on Friday night. Of note, an isolated yet destructive size 3 natural persistent slab avalanche was reported this week in the South Chilcotin area north of Goldbridge. The avalanche failed on surface hoar buried in early February. Cornices are large and fragile, and may also fail under the weight of a person.
Snowpack Summary
Continued moderate snowfall and strong southerly winds have formed reactive storm slabs on lee and cross-loaded alpine and treeline features. The upper snowpack sits above a crust that was reported on all aspects and elevations with isolated pockets of surface hoar in high north facing terrain that stayed cool prior to the storm. The mid and lower snowpack are generally well settled. That said, a layer of surface hoar buried at the beginning of February is a concern in the South Chilcotin area and can be found about 80cm below the surface. Although this layer is isolated, it has been responsible for destructive natural avalanche activity and is worth keeping on your radar if you're headed to the north of the region.
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.