Regions
Banff Yoho Kootenay.
Conditions are highly variable right now, and the danger ratings represent the highest danger rating for the day. Avalanche danger is lower in the morning when the snow surface is frozen, and before the air temperatures warm up. Start early.
Weather Forecast
Clearing through the day on Wednesday, with sun patches appearing in the afternoon. Expect a high of 0 degrees at treeline, and lows of -10 early in the morning. Trace amounts of snow expected overnight for Wednesday.
Snowpack Summary
The snowpack is a real mixed bag right now: totally dependent on aspect and elevation. At treeline and above, 5-10 cm of new snow overlies a strong melt-freeze crusts to ridge top on solar aspects, and 2000m on north aspects. Below treeline the snowpack becomes wet through the day. The snowpack has not converted to spring conditions yet.
Avalanche Summary
No new avalanches reported or observed today.
Problems
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
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.