Avalanche conditions could vary dramatically between aspects and elevations. Triggering large avalanches is still possible. Remain diligent and continue to make conservative decisions.
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Saturday
Weather Forecast
SATURDAY: Mainly cloudy with continued light snowfall bringing another 1-3cm of accumulation. Freezing levels around 1300m and winds are expected to be moderate from the west. SUNDAY: Another 5cm possible overnight before continued light snowfall brings1-3cm of accumulation throughout the day. Freezing levels rising throughout the day to as high as 1500m and continued moderate westerly winds. MONDAY: Light to moderate snow with freeing levels around 1800m.
Avalanche Summary
A natural Size 1.5 avalanche was observed in the Kicking Horse slackcountry on Thursday that apparently ran on a reloaded bed surface in a wind loaded feature. The interface is suspected to be the early January weak layer. Natural persistent slab avalanche activity was also observed earlier in the week, with a report of two Size 2.5s also in the Kicking Horse backcountry, that also released on the surface hoar, facet and crust weakness as deep as a meter down.
Snowpack Summary
A supportive crust (in most places aside from shaded aspects at treeline elevations) and perhaps new surface hoar (where it survived the heat, rain and sun) could be buried by as much as 5-10cm of fresh snow or deeper wind slabs. The early January surface hoar/ facet layer is typically down 70-90 cm. Recent avalanches have been failing on this interface in the north of the region (see avalanche discussion) and it continues to produce sudden planar results in snow pit tests. In general, the lower snowpack is well settled and strong, apart from some thin snowpack areas where basal facets exist.
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.
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.