Avalanche Forecast

High -

Friday night: Flurries bringing 5-10 cm of new snow. Strong southwest winds.Saturday: Mainly cloudy with scattered flurries bringing approximately 5 cm of new snow. Moderate to strong southwest winds. Freezing level to 500 metres with alpine temperatures of around -8.Sunday: Cloudy with sunny periods and isolated flurries bringing a trace of new snow. Light to moderate south winds. Freezing level dropping to near valley bottom with alpine temperatures of around -10.Monday: Mainly cloudy with isolated flurries and a trace of new snow. Light to moderate southwest winds. Alpine temperatures of around -11.

Thursday's reports include observations of several natural storm slab and wind slab releases ranging from Size 1.5-2.5. One remotely triggered Size 1.5 was also noted. All aspects saw fairly equal representation and crown fractures reached as deep as 50cm, demonstrating the impact of recent wind loading.A number of notable persistent slab avalanches were reported last week. This included natural activity on the western slopes of the Purcells (two Size 2.5 avalanches on the February 3rd surface hoar and one size 3.5 avalanche on the November crust) and two large skier triggered avalanches near Golden (including a size 3 remotely-triggered avalanche on the mid-January interface). Triggering a persistent slab avalanche is an ongoing low probability - high consequence scenario that requires a cautious approach to terrain selection, especially as ongoing snowfall continues to undermine stability by adding load to the snowpack.Looking forward, conditions on Friday night look prime for producing fresh, touchy wind slabs as snowfall rates peak under continuing strong winds.

Stormy weather since Tuesday night has delivered a wide ranging 10-30 cm of new snow to the region, burying widely reported faceted surface snow as well as surface hoar recently reported at about 3mm on shaded aspects in some areas. Moderate to strong southerly winds have accompanied the new snow, promoting the formation of touchy wind slabs in lee areas at upper elevations. About 30-70 cm below the surface you'll likely find the mid-February interface which is composed of a thick rain crust up to about 2000 m, sun crusts on steep solar aspects, and spotty surface hoar on shaded aspects. Several deeper weak layers remain a concern including the February 3rd surface hoar layer (40-90 cm deep) in the southern Purcells, and the mid-January surface hoar layer in the northern Purcells (about 100 cm deep). Basal facets may still be reactive in shallow rocky start zones.