Regions
Banff Yoho Kootenay.
Solar radiation will be a major factor over the coming days. Be mindful to stay clear of south aspects in the hottest part of the day.
Weather Forecast
Freezing levels, by some small miracle, will remain about 0 in the valley bottoms until Friday. However, a clearing trend will allow for intense solar radiation over the next few days. It will be best to avoid south aspects in the hottest part of the next few days.
Snowpack Summary
The tipping point in the stability of the snowpack has been reached. The past week's 60 cm of storm snow has settled into a slab which is reacting to natural and skier triggers with failures occurring deep in the snowpack. This situation is expected to continue through Wednesday, with extra care advised in all avalanche terrain.
Avalanche Summary
Explosive control on Mt Stephen produced avalanches up to size 2 today. Also, on Wapta peak a cornice dropped and produced a size 2 in extreme terrain within the last 36 hours. On a flight through Yoho evidence of a wide spread cycle up to size 3 was observed that likely occurred in the last 3-4 days.
Confidence
Freezing levels are uncertain on Wednesday
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
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.