Regions
Banff Yoho Kootenay.
Avalanche conditions are slowly improving. Today was the first day with no new avalanches observed, so the natural cycle is over, but human triggering remains likely. Continue to minimize your exposure to avalanche terrain unless it has already slid.
Weather Forecast
Snowfall expected over the next few days, with 5 cm on Tuesday, 10 cm on Wednesday and 3 cm on Thursday. Freezing levels should reach 1800m each day, with alpine temperatures ranging from -1 to -12. Winds are generally moderate but will pick up to strong through Tuesday night.
Snowpack Summary
10 cm of snow sits over a solid 100cm+ slab which rests precariously over the weak basal facets at treeline and above. Tests produce consistent sudden collapse results in the facets, and this will not become stronger soon. The surface snow is of a mix of soft snow in the shade, melt-freeze snow below treeline, and sun crust on sun exposed slopes.
Avalanche Summary
No new avalanches were reported or observed today. This is the first day in about two weeks that we have not seen, or heard of a fresh avalanche in our forecast 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.
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.