Regions
Banff Yoho Kootenay.
The limited amount of information available to forecasters points to a reactive crust and facet layer near the base of the snowpack. Use caution particularly as you transition into the alpine.
Weather Forecast
A weak, fast moving low will pass North to South over the Rockies overnight potentially bringing trace amounts of precip, winds shifting to the North and dropping temperatures into Sunday. Behind this, a ridge will dominate the weather until mid week.
Snowpack Summary
In the alpine, 20-50cm with variable wind effect sits on the Oct.26th temperature crust which can be found mainly on shaded aspects in the alpine and is a few cm thick above weak facets. Total snowpack depths are 60-120cm+ in the alpine, tapering dramatically at treeline to below threshold values for avalanche below treeline.
Avalanche Summary
No new avalanches reported today. There have been several avalanches on the Oct 26 interface over the last week. This includes skier remote triggered avalanches to size 2 along hwy 93N, remote triggered avalanches to size 2.5 resulting from explosives at the Lake Louise ski hill, and several natural events seen through the region.
Confidence
Due to the number of field observations
Problems
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.
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.