Regions
Banff Yoho Kootenay.
5-15 cm has fallen in the last few days and has created touchy wind slabs on NE features. LP
Weather Forecast
Continued light flurries, warm alpine temperatures (-6C), and light to moderate west winds with strong gusts expected for the next 2 days. We may see more intensive flurries on Sunday adding to the existing storm and wind slabs and in turn increase the avalanche hazard.
Snowpack Summary
There is 50-70 cm of snow at tree line which is generally weak, and facetted, but there is some mid-pack support. Some fresh wind and storm slabs exist in lee alpine terrain which may be reactive to skier triggering. The October crust is 10-20 cm from ground and producing mod-hard results with comp. test.
Avalanche Summary
No new natural avalanche activity observed in the last several days. Sunshine forecasters reported ski cutting a size 1.5 avalanche in previously worked terrain. It was a 10-15 cm thick storm slab over a wind slab, which stepped down to the basal rain crust or facets. It was on a lee NE facing alpine feature.
Confidence
Track of incoming weather systems is uncertain
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.