Winds have created a variable snowpack. Be alert to conditions that change with aspect and elevation.
Confidence
Fair - Intensity of incoming weather systems is uncertain
Weather Forecast
Generally light precipitation is expected on Wednesday, with the freezing level around 1700 m and winds light to moderate from the S to SW. Moderate snow is expected on Thursday and Friday (5-10 cm /day) above about 1800 m (rain at lower elevations). Winds are moderate to strong from the S to SW.
Avalanche Summary
A cycle of wind slabs and storm slabs (most size 1, up to size 2) was reported on Sunday and Monday. These failed naturally and were triggered remotely by skiers as well. Many were on north aspects. A snowmobiler also triggered an avalanche on Sunday (see https://bit.ly/19wEv36).
Snowpack Summary
Wind slabs and wind-affected surfaces are the main theme at the snow surface. Cornices may also be fragile. Older, buried wind slabs may be hard to spot. A crust/facet combo down 10-60 cm produces moderate, sudden results in snowpack tests. In the neighbouring Sea-to-Sky region, this layer has shown enough reactivity to call it a persistent slab problem. Maybe it is the same inland? Let us know. A second, deeper crust, marks the boundary with a lower snowpack that is reported to be generally well-settled and strong. Below treeline, the diminishing snowpack is trending isothermal (same temperature throughout).
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.