One more day of cool weather until rising temperatures elevate the danger.
Confidence
Moderate - Freezing levels are uncertain on Tuesday
Weather Forecast
MONDAY: Increasing cloud throughout the day, moderate southwest winds increasing throughout the day, alpine temperatures around -8 and warming overnight.TUESDAY: Flurries with up to 5 cm of new snow, strong southwest winds, freezing level rising to 1600 m.WEDNESDAY: Continued flurries with minor accumulations, strong southwest winds, freezing levels steady around 1600 m.
Avalanche Summary
Several size 1-1.5 natural loose dry avalanches were reported on solar aspects over the weekend. On Saturday, ski cutting produced a size 2 avalanche on a wind-loaded northeast aspect at 1900 m. The avalanche was suspected to release on a weak layer of facets underneath the wind slab.On Monday, expect wind slabs to remain reactive to human triggers on a variety of aspects.
Snowpack Summary
Up to 20 cm of recent storm snow has buried a plethora of old surfaces (wind scoured, old wind slabs, surface hoar up to 20 mm in sheltered terrain, and/or faceted old snow). Moderate winds from all directions have formed widespread wind slabs which can be found on lee slopes and behind mid-slope terrain features. Deeper in the snowpack, the mid-December persistent weak layer of facets has been more prominent and reactive in the Corbin area than areas closer to Fernie. The layer is generally considered dormant at the moment in deeper snowpack areas, but its status may change as the temperatures warm this week.
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.