Confidence
Fair - Timing of incoming weather is uncertain
Weather Forecast
Friday: Cloudy with flurries. Freezing level near valley floor. Light to moderate winds.Saturday: Light to moderate snow. Freezing level rising to 700m by evening. Strong to gale westerly winds. Sunday: Moderate (locally heavy) precipitation with the freezing level climbing to 1500m by afternoon. Strong to gale westerly winds.
Avalanche Summary
A few natural avalanches, up to size 2, were observed in steep lee (wind-loaded) terrain on Wednesday. Whumphing was observed below treeline.
Snowpack Summary
Up to 80cm of snow has fallen since Monday. Strong winds have created hard slabs, soft slabs and fragile cornices. The freezing level went up to about 1000 metres early Wednesday morning. Snowpack tests give easy to moderate results on several layers in the upper snowpack. Key concerns as further snow builds this weekend include a weak facet layer that was created during the brutal cold snap in mid-January and a buried crust.
Problems
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.
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.