Regions
Northwest Coastal.
Confidence
Fair - Intensity of incoming weather is uncertain on Friday
Weather Forecast
Thursday night/ Friday: 15cm of snow / Moderate to strong southwest winds / -12.0 at 1500mSaturday: Light snowfall / Moderate northerly wind / -12.0 @ 1500mSunday: Clear skies / Light northerly winds / -18.0 @ 1500m
Avalanche Summary
Several size 1's reported on wednesday in the top 10cm in wind affected areas. Expect significant wind slab activity with forecast snow and wind on thursday night.
Snowpack Summary
Some areas (Terrace, Kaziks) are reporting an alpine snowpack of 5 metres. In these areas the mid-december surface hoar-facet layer is buried down about 250 cm and has not been reactive for quite some time. At this time the biggest issue in the region seems to be new snow instabilities. Although they can be quicker to heal than other weaknesses, they may be highly destructive, especially with this season's pattern of heavy accumulations of snow combined with strong winds.Areas that experienced very strong winds during the recent storm may have thick windslabs that may take another couple of days to settle. Be cautious of large, recently developed cornices. They may be destructive by themselves, or they can become a trigger for an avalanche on the slope below.The mid and lower snowpack is generally well settled and strong.Expect significant new wind slab development with forecast wind and snow.
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.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.