The timing and intensity of snowfall forecast for Friday and Friday night is highly uncertain. Pay close attention to how much snow falls in your riding area and be prepared to back-off to simple terrain.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain on Friday
Weather Forecast
Weather models are calling for 5-10cm of new snow on Friday morning with heavy snowfall (up to 35cm) on Friday night and into Saturday morning. Generally light flurries are forecast for the rest of Saturday while up to 20cm of new snow may fall between Saturday night and Sunday. Ridgetop winds on Friday will be extreme from the south, becoming light on Saturday and Sunday. Freezing levels will hover around 1500m for the forecast period. Note: The timing and intensity of precipitation on Friday is highly uncertain.
Avalanche Summary
Artificially and naturally triggered storm slab avalanches continue to be reported. Of note, a size 2 storm slab avalanche was remotely triggered on a north-facing treeline feature from a distance of 150m in the Coquihalla area. Additionally, a skier was caught in a size 2 storm slab avalanche on a northwest-facing treeline slope in the Duffey lake area. The individual was not injured in the slide. These avalanches, which occurred on Wednesday, highlight the potentially touchy conditions in some areas. Cornices are large and fragile, and may also fail under the weight of a person.
Snowpack Summary
Up to 50cm of new snow and strong winds have formed widespread reactive slabs. 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-pack is generally well settled. A layer of surface hoar buried in early January can now be found down 1-2 meters. In most places this layer was flushed-out by rain. However, in the north of the region it remains a low probability/high consequence concern, producing isolated hard sudden planar shears in snow pit tests.
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.