Regions
Northwest Coastal.
Large amount of new snow, strong winds, and rising temperatures make for text-book high avalanche hazard. Careful and conservative terrain choices are essential now.
Confidence
Fair - Due to the number and quality of field observations
Weather Forecast
Precipitation and strong winds should ease off late today (Friday) and skies should clear early on Saturday and begin to dry out the region for a few days. Freezing levels have been around the 1500M mark , but should drop to around 500m for Saturday and Sunday.For more information check out the Mountain Weather Forecast at: https://avalanche.ca/weather
Avalanche Summary
Explosive control by a commercial operator yesterday produced numerous size 1.5 to 2 avalanches in the recent storm slab 23 to 35cm thick. In the Ningunsaw, several size 2 moist avalanches were observed.
Snowpack Summary
This storm system accompanied by strong southwest winds has built dense slabs on lee features, and added additional load to the previous storm slab. There are a variety of old buried interfaces that include hard wind slabs, hard crusts, surface hoar, and/or surface facets. The recent lack of large avalanches suggests reasonable bonds at these interfaces, but we should remain cautious of steeper, high-consequence slopes. A release on any of these buried layers could be large and destructive . At the base of the snowpack, weak facets may be found, particularly on shallow alpine slopes in the north of the region. Cornices are continuing to grow and will be potentially unstable. Recent rapid loading and rising temperatures through Friday are a major concern right now. Operators are estimating 50+cm of storm snow at upper 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.