Regions
Banff Yoho Kootenay.
Incoming storm will raise the alpine danger over the next few days. Pull back the reigns and let the storm settle out. Watch for early season hazards!
Weather Forecast
Low pressure system approaching from the coast. Forecasts are calling for 15 cm of snow Monday, and another 5 cm on Tuesday and Wednesday in the northern part of the bulletin region, with less in the south and east. Freezing levels will be highest on Monday (1900m) and falling back to 1200m Tues and Wed. Alpine winds will be strong from the S.
Snowpack Summary
An average of 30-50 cm of snow at treeline with up to 100 cm in alpine locations. A crust formed prior to Halloween is down 10-15 cm helping provide support for skiers. This crust disappears on N aspects around 2500m. Previous alpine winds have created pockets of wind slab. On glaciers be wary of the ice-snow interface and check it for instability.
Avalanche Summary
Nothing new observed in Field area and on a flight from Banff to Bow Summit.
Confidence
Intensity 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.