Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Regions
Banff Yoho Kootenay.
Great skiing with the fresh snow, but make conservative terrain choices. Natural activity has slowed but the potential to trigger large avalanches is still very real. Conditions will remain this way for some time.
Weather Forecast
A mix of sun and cloud with a few light flurries are forecast over the next few days. Winds should stay in the light range and temperatures are expected to be in the -3 to -12 range with a slow decrease over the forecast period.
Snowpack Summary
Another 5-10cm overnight with light winds. Isolated soft slab formation near ridge crests in the alpine. Persistent problems remain with the lower half of the snow pack being weak and faceted especially in thin areas or near rocky outcrops. Cooler temperatures have helped to stabilize the snow pack below tree line but it is still very weak.
Avalanche Summary
Two notable events in the last 24hrs. One was a remotely triggered size 3 avalanche near Cirque peak triggered by a large whumph almost 200m away. The second was two large avalanches triggered by explosives in "the Elevator Shaft" at Lake Louise after numerous smaller explosives had been tried in the previous 24hrs. All ran on the weak facets.
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.