South Columbia

Favourable travel conditions will hang on for another day. Maintain discipline and normal cautions to manage small and lingering mountain hazards.

High -

Wednesday: Mainly cloudy with isolated flurries and a trace of new snow. Light southwest winds, increasing overnight. Freezing level to 1700 metres with alpine high temperatures around -2.Thursday: Cloudy with wet flurries bringing 4-8 cm of new snow to higher elevations, with rain below about 1700 metres. Precipitation increasing and snow line falling overnight. Moderate to strong southeast winds. Freezing level to 2100 metres with alpine high temperatures around 0 to +1.Friday: Mainly cloudy with continuing isolated flurries and 3-5 cm of new snow. Moderate southwest winds. Freezing level to 1200 metres with alpine high temperatures around -5.

Reports from Monday included a few small (size 1-1.5) skier-triggered wind slabs and storm slabs as well as small ski cut and natural loose dry releases. These all occurred in steeper terrain on a wide range of aspects.On Saturday there were several reports of solar-triggered loose wet avalanches as well as cornice and glide crack failures up to size 3 on predominantly south to west aspects at all elevations.Last Friday there were reports of natural cornices failures up to size 2 on north and northeast facing slopes in the alpine that had little effect on the slopes below, while explosive control produced only small (size 1) storm slabs on similar aspects.

Recent light snowfalls (10-20 cm) have been followed by warm daytime temperatures and glimpses of sun, setting up a couple of thin storm snow layers over temperature and sun crusts on south aspects. On shaded aspects at higher elevations, the recent snow has buried a couple of surface hoar layers now found up to 30 cm deep. Mainly small loose dry releases have been observed on the shallowest of these layers (down about 10cm), while the deepest (down 30 cm) has been the failure plane in a few slab avalanches in adjacent regions. New snow amounts taper with elevation and below 1900 m, minimal accumulations have buried a supportive crust on all aspects. This crust will likely break down with daytime warming, becoming moist in the afternoon. Deeper persistent weak layers from January and December are generally considered dormant, but could wake up with a surface avalanche stepping down, large cornice fall, or a human trigger in a shallow or variable-depth snowpack area. These layers consist of sun crust, surface hoar and/or facets.