Avalanche Forecast

Fair - Timing or intensity of solar radiation is uncertain

Friday: Lingering cloud and flurries. Generally light winds. Freezing level around 1000m.Saturday/Sunday: Sunny. Light southerly winds. Freezing level rising to around 1500m in the afternoon and falling to valley floor at night. On Sunday afternoon, freezing level is forecast to rise to around 2000m.

There have been four close calls in the Purcell Mountains this week, all involving very large slabs releasing either from a distance or with a light load. This is a scary situation. On Thursday, a snowmobiler remotely triggered a size 3.5 slab on an east aspect at 2400m at Old Man, east of Quartz Creek. It failed 1-2 m deep, was 200-300 m wide and ran full path, taking out mature timber. A second slope also failed, either remotely or sympathetically. In the Dogtooth Range on Tuesday, a size 3 slab was triggered by a skier on a north aspect. It's suspected to have initiated on the February weakness, and stepped to ground. Two large slabs (size 2-2.5) also released naturally on north to north-east aspects, up to 1 m deep. On Sunday, there were two snowmobile-triggered size 3 avalanches on west aspects in the southern Purcells near Kimberley (read more in 'related incidents' on this page). Strong solar warming forecast for the weekend is only going to make conditions trickier, decreasing stability on solar aspects which could step down to persistent weaknesses and create very large avalanches. All other aspects have also proven that they can fail as deep persistent slabs. I'd be extremely wary of any large slope and consider choosing a deeper, stronger snowpack region than the Purcells to play in this weekend.

Recent snow and wind created mostly small, soft wind slabs. Deeper in the snowpack, the major concerns are the mid-February persistent weak layer, buried 1-2 m deep, and facets at the base of the snowpack. The February layer demands respect right now. It is very touchy and can be triggered remotely or by a light load on a variety of aspects, creating frighteningly large avalanches.