Cloudy skies Saturday night combined with high freezing levels on Sunday will increase the likelihood of large natural and human triggered avalanches. Avoid slopes with overhead exposure where falling cornices could trigger large avalanches.
Weather Forecast
Clouds may roll in overnight on Saturday which would likely result in poor "crust recovery" overnight. Freezing levels are forecasted to rise to 2200m on Sunday with flurries producing a bit of snow in the afternoon/evening. Monday looks cloudy with slightly lower freezing levels. Tuesday is should be clear and cool with freezing levels dropping sharply. Light to moderate southerly winds until Monday evening when they drop off.
Avalanche Summary
On Friday, near Valemount there was a small point release loose wet avalanche that went airborne over cliffs and triggered a size 2 slab avalanche on the late February weak layer. Small loose wet avalanches and failing cornices triggering slab avalanches on the late February layer would be on the forefront of my mind as I travel through the mountains this weekend.
Snowpack Summary
At ridgetop, cornices are huge and could become increasingly touchy with forecast solar radiation. Old wind slabs still linger on lee features at treeline and in the alpine. 70-100cm below the surface you'll find a persistent weak layer comprised of surface hoar, facets and/or a thick crust. This layer seems variably reactive. In other words, it's still really touchy in some places while in other spots it's really tough to trigger, and there's not much of a reliable pattern telling us what exact aspects are most suspect. I'd continue to be suspicious of steep, unsupported features at treeline and in the alpine as this layer has the potential to produce very large avalanches.
Problems
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.
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.
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.