Regions
Northwest Coastal.
Forecast snowfall amounts are highly uncertain. If more than 20cm falls in your area, the Avalanche Danger may be High.
Confidence
Fair - Forecast snowfall amounts are uncertain on Thursday
Weather Forecast
A pacific storm will intensify on Wednesday night bringing snowfall to the region for Thursday and Friday. A clearing trend is forecast for Saturday. Up to 25cm of snow is forecast for Wednesday night and Thursday. Around 5cm of snow is expected on Friday. Only light flurries are forecast for Saturday. Ridgetop winds should remain strong to extreme from the southwest. Freezing levels are expected to hover between 1200m and 1500m with Friday being the warmest day.
Avalanche Summary
A skier recently triggered a size 1 wind slab in the alpine. Explosives control on Sunday triggered several very large avalanches near Stewart, failing at ground or on a deeply buried crust. New snow and wind on Wednesday night and Thursday is expected to promote a new round of storm slab activity.
Snowpack Summary
Around 1 m of recent storm snow was redistributed by strong and variable winds, creating widespread wind slabs. Operators now report reasonable settlement and bonding within the storm snow. Older buried surfaces include wind slabs, hard crusts, surface hoar, and/or surface facets. With more snow and wind forecast for Thursday, new storm slabs are expected to form. The mid-pack is generally well-settled and strong. At the base of the snowpack, weak facets may be found, particularly on shallow alpine slopes in the north of the region. Cornices are large and potentially fragile. Below treeline, the snow appears to be in a spring melt-freeze cycle.
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.