Another warm day with high freezing levels is forecast for Saturday. Watch for moist or wet snow early in the day if there is not a good re-freeze overnight.
Confidence
Moderate - Freezing levels are uncertain on Saturday
Weather Forecast
Overnight: Some cloud developing overnight that may limit crust development. Saturday: Mostly clear or scattered cloud with strong westerly winds and daytime freezing up to 2200 metres. Sunday: Mostly cloudy with 3-5 cm of convective flurries and moderate gusty west winds. Daytime freezing around 1500 metres. Monday: Re-freeze to valley bottom expected. Chance of snow developing from the northeast.
Avalanche Summary
On Friday in the Elk Valley North area, there were numerous loose wet avalanches up to size 2.0 at all elevations on solar exposed aspects. The valley fog in the morning may have reduced the effects of the sun below treeline.
Snowpack Summary
On Friday, the sun was strong at higher elevations and the surface snow became moist or wet in the Elk Valley North. Castle Mountain reported 26 cm of new snow overnight, that I suspect must have settled rapidly due to the strong sun and high freezing levels. On Thursday in Crowsnest North, the sun was strong in the morning and solar aspects became moist up into the alpine. There was still some dry snow on north aspects in the alpine. The bottom third of the snowpack is composed of weak facets and full-depth avalanches over this basal weakness remain a concern, and may be triggered by large loads like cornice falls, or strong solar radiation on a clear day.
Problems
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.
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.
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.