Purcells

Convective snowfall will make for variability both in snowfall and avalanche danger. Consider danger to be HIGH in areas that get over 30 cm of new snow. South aspects may be extra touchy where new snow buries yet another crust.

Moderate - Forecast snowfall amounts are uncertain

Sunday night: Isolated convective flurries bringing 5-20 cm of new snow. Light variable winds.Monday: Mainly cloudy with lingering isolated flurries and a trace of new snow. Light northeast winds. Alpine high temperatures around -11.Tuesday: A mix of sun and cloud. Light southwest winds. Freezing level to 800 metres with alpine high temperatures around -9.Wednesday: Cloudy with isolated flurries and a trace of new snow, increasing overnight. Freezing level to 1300 metres with alpine high temperatures around -6.

On Saturday a skier triggered a large slab avalanche (size 2.5) on a south aspect at 2600 m. The avalanche failed on a buried sun crust 150-200 cm below the surface. Another large (size 2.5) wind slab released naturally from a steep southeast-facing alpine slope in the St. Mary's area. Explosives control in the northern half of the region produced numerous storm slabs ranging from size 1.5-2.5 at treeline and alpine elevations. Crown fractured ranged from 30-100 cm. All aspects were represented in results, with the majority of activity focused on northeast to northwest aspects in the alpine.Several size 1-2 natural wind slabs and storm slabs were reported on a range of aspects on Thursday and Friday. A few size 1 skier triggered slabs on were reported on south aspects around 2300 m, including one that partially buried a skier.On Wednesday, several skier triggered avalanches up to size 2.5 were reported from all aspects above 2000 m. These avalanches predominantly failed on the late-March interface, with crown depths from 20-50 cm deep and up to 100 cm in some areas.

Light new snow amounts have begun to accumulate over wind-affected surfaces as well as a new crust on solar aspects. Below the surface, accumulations from last week vary from up to 80 cm amounts in areas just east of Kootenay Lake to a mere 20-40 cm in eastern parts of the region. The storm snow sits on an interface buried in late-March that consist of crusts below 1900 m and on south aspects, and surface hoar on shaded aspects at higher elevations. Other slightly deeper surface hoar/facet layers have been reported on shaded aspects at higher elevations and may be found approximately 40-60 cm below the surface.Deeper persistent weak layers from mid-late February as well as January and December layers, are still being monitored by professional observers, but are generally considered dormant. Facets also linger at the base of the snowpack.