Friday was an active day for avalanches. Gather information to supplement this forecast as you travel and be especially tuned in to signs of instability.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
Friday night: Mainly cloudy with isolated flurries and a possible trace of new snow. Light north winds.Saturday: A mix of sun and cloud. Light northwest winds. Alpine high temperatures of -7.Sunday: A mix of sun and cloud. Light southwest winds. Alpine high temperatures of -4.Monday: Mainly cloudy with isolated, increasingly wet flurries as freezing levels rise to 2500 metres. Strong southwest winds and alpine high temperatures reaching 0.
Avalanche Summary
Preliminary reports since Friday's new snow show a natural avalanche cycle during the Friday overnight period as well as explosives control in the Fernie area producing storm slab releases to size 2. Visibility of the extent of avalanche activity remained limited on Friday.
Snowpack Summary
Moderate to heavy snowfall over Thursday and Friday brought about 30 cm of new snow to the region. This new snow has now buried a recently formed layer of weak, feathery surface hoar previously found on the snow surface. Below this layer of surface hoar, the new snow has also buried pockets of recently reactive wind slab in wind-exposed alpine and treeline terrain. This wind-affected layer sits above a complex of late-October and early-November melt-freeze crusts and facets. The snowpack is deepest at alpine and treeline elevations, where you might now expect to find total depths of around 70 cm. These depths taper rapidly with decreasing elevation.
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.