Regions
Banff Yoho Kootenay.
Good spring conditions exist. Recent storm snow has created wind slabs in open areas above treeline. Solar effect will become more of a concern throughout the week. JBW
Weather Forecast
Cool north westerly flow will prevail until Wednesday as a ridge becomes anchored off the coast. Unsettled conditions will bring convective flurries. The ridge builds inland for a significant warm up by Wednesday-Thursday.
Snowpack Summary
Cooler conditions should keep the crust solid for much of the day. Recent snow has created wind slabs just below ridge crests up to 30-40 cm thick. These slabs have been more touchy on southerly aspects where they overly a crust, but could be triggered on northerly aspects as well. Solar effect will loosen up the recent new snow on steeper terrain.
Avalanche Summary
Several small skier triggered windslabs up to size 1.5 have been reported over the last few days. These have been triggered on steep terrain just below ridgecrests. Storm snow over crust is the main ingredient.
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.