Regions
Northwest Coastal.
Snow! Finally! But also elevated avalanche danger. Play safe.
Confidence
Fair - Forecast snowfall amounts are uncertain on Sunday
Weather Forecast
Snowfall tapers to light flurries on Friday and Saturday, before the next storm system arrives on Sunday, bringing moderate snow. Winds are moderate to strong throughout the period, switching from SW to NW on Saturday, and back to SW on Sunday. The freezing level climbs to near 1500 m ahead of Sunday’s storm but drops with the arrival of precipitation.
Avalanche Summary
At the time of writing, no avalanches have been reported, but I expect a natural cycle occurred today in response to snow and wind-loading.
Snowpack Summary
New snow and strong SW winds are likely to have built wind slabs on lee features, and storm slabs in more sheltered spots. These overlie a variety of interfaces including old hard wind slabs, a sun crust, a rain crust, surface hoar, and/or surface facets. At the base of the snowpack, weak facets may be found. Keep an eye out for cornices that could fail.
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.