Avalanche Forecast

Moderate -

Wednesday night: Mainly cloudy. Light southwest winds, increasing to strong northwest in the alpine.Thursday: A mix of sun and cloud. Light southwest winds, increasing to strong northwest in the alpine. Alpine temperatures starting around -9 and rising by a few degrees in the afternoon.Friday: A mix of sun and cloud. Strong northwest winds decreasing over the day. Alpine high temperatures around 0 as freezing levels rise to about 2000 metres.Saturday: Mainly sunny. Moderate to strong west winds. Alpine high temperatures around +3 with freezing levels reaching a possible 2900 metres.

New snow was reactive on Sunday with several reports of skier-triggered, cornice-triggered, and natural avalanches. On Monday, explosives triggered size 2 storm slab avalanches and cornices. A weak layer of surface hoar buried 10-30 cm is responsible, especially around treeline 1500-1900 m. Most storm slab avalanches are reported on north-northeast aspects 1700-2000 m. However 2 recent avalanches occurred on southerly aspects. On Sunday, a size 2 avalanche released naturally around 2000 m on a southeast aspect with solar input with surprising propagation. On Monday, a snowboarder triggered a size 2 avalanche on a south aspect in open trees outside the Fernie boundary, fortunately with no injury. Two large snowmobile triggered avalanches were reported over a week ago. One was triggered on a thin, rocky, southwest facing feature near ridge crest north of Fernie (report here). The other was triggered on a wind affected south facing slope at treeline in the Corbin area (report here). Deep persistent slab activity has been most common in parts of the region with shallow snowpacks (such as near the continental divide) and alpine features with thin variable snowpack depths.

Flurries with strong winds overnight brought recent snowfall accumulation to around 10-30 cm. In alpine and treeline areas, winds are redistributing storm snow loading lee terrain features and building cornices. Lower down, the recent snow is sitting over a weak layer of surface hoar and sun crusts. The surface hoar is most prominent around treeline elevations (1500-1900 m). On solar aspects and below treeline, the surface hoar and new snow overlie sun and temperature crusts.In shallow snowpack areas, the base of the snowpack may still be composed of weak faceted grains. In deeper snowpack areas, the middle and lower portions of the snowpack are generally considered to be well-settled and strong.