Make conservative terrain choices because the storm snow will take longer than usual to settle.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
WEDNESDAY: Sunny, light north winds, treeline temperatures at -8.THURSDAY: Flurries with accumulations of 5-15 cm by the afternoon, 30-50 km/h southwest winds, treeline temperature at -6.FRIDAY: 20-50 cm of new snow, 20-40 km/h southwest winds, treeline temperature at -4.
Avalanche Summary
On Monday, storm slabs were very touchy with numerous size 1 skier triggered avalanches running on all aspects, and several size 1.5-2 avalanches triggered remotely. The avalanches were running on a widespread melt-freeze crust below the storm snow, which will continue to be touchy with human triggers.
Snowpack Summary
Monday delivered 40-60 cm of new snow to the South Coast, with the heaviest accumulations on the North Shore. The new snow likely sits above a supportive melt-freeze crust, providing a bed surface for storm slabs to run on. The new snow was not bonding well with the crust on Tuesday, and may take longer than usual to stabilize due to the cold arctic air currently over the region. The lower snowpack is well settled and strong. Total snowpack depths are 160-200 cm at treeline, with isolated pockets deep enough for avalanches at below treeline elevations.
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.