Regions
Northwest Coastal.
Dangerous storm slabs will develop this week. Stick to conservative terrain during the storm.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
WEDNESDAY: Flurries start Thursday night delivering 20-40 cm of snow by Wednesday afternoon, strong south wind, freezing level around 700 m.THURSDAY: Another 10-30 cm of snow, strong south winds, freezing level steady at 700 m.FRIDAY: Light flurries, moderate southeast winds, freezing level around 500 m.
Avalanche Summary
No recent slab avalanches have been reported. A natural cycle of wet loose avalanches (up to size 2.5) occurred on steep solar aspects over the weekend. Expect a spike in activity with the incoming storm.
Snowpack Summary
New storm slabs are developing, with extra thick and reactive slab in lee areas. The new snow is falling on a mix of old wind slabs and temperature crusts left over from the weekend. Professionals have been monitoring a few layers in the upper snowpack, including crusts and surface hoar layers buried 40-80 cm below the surface. Although these layers have been reactive in recent snowpack tests, they have not produced avalanches lately. The lower snowpack is generally strong, with the exception of areas around Stewart and further north where a basal crust and facets exist.
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.