Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural and human triggered avalanches likely.
Below Treeline
Natural and human triggered avalanches likely.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural and human triggered avalanches likely.
Below Treeline
Natural and human triggered avalanches likely.
Regions
Banff Yoho Kootenay.
Touchy conditions persist. If avalanches are triggered, expect deep fractures and wide propagations. The better choice is to avoid avalanche terrain.
Weather Forecast
The next storm should arrive early Wednesday. By Thursday we could see accumulations of up to 35cm. Moderate wind from the SW and temps near zero will accompany the storm cycle.
Snowpack Summary
Storms from the last 9 days have deposited up 100cm of storm snow. The main concern in the snowpack lurks below and continues to be the 3 persistent weak layers of surface hoar and/or facets that are found between 50 and 100cm down. We continue to observe sudden test results, whumphing and large propagations on these layers.
Avalanche Summary
Lake Louise ski area reported triggering a large size 3 avalanche with explosives today. At the very end of the day Visitor Safety responded to a potential involvement on Quartz Ridge. It ended up be a remote triggered size 3 from a recreational party with no involvement.
Confidence
Intensity of incoming weather systems is uncertain on Thursday
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.
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.