There is a lot of uncertainty surrounding the intensity of precipitation amounts in the region. Certainly if the freezing level rises in combination with the potential for heavy snowfall and strong winds, the avalanche danger will be elevated.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain on Wednesday
Weather Forecast
WEDNESDAY: Snow, accumulation 25-40cm with rain possible at lower elevations, strong southwest winds, freezing levels around 1600m.THURSDAY: Snow in the overnight period Wednesday into Thursday morning, accumulations 10-20cm. Cloudy with isolated flurries Thursday during the day, strong southwest winds, freezing levels around 1400m.FRIDAY: Mainly cloudy with the possibility of isolated flurries, light southwest wind and freezing level around 1000m.
Avalanche Summary
Several natural and human triggered size 1 wind slabs were reported on Monday. Expect fresh wind slabs to form and avalanche activity to increase as the wind continues to blow and snow starts to fall Tuesday evening through Wednesday.
Snowpack Summary
Recent winds have caused widespread wind affect in exposed alpine and tree line terrain forming touchy wind slabs on lee features. These are now buried by a blanket of new snow. Last week's 20 cm of low density snow buried a variety of old surfaces (wind scoured, old wind slabs, surface hoar up to 20 mm in sheltered terrain, and/or faceted old snow). 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 throughout the week.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.