Avalanche Forecast

Moderate -

Monday: Cloudy with scattered flurries bringing up to 5 cm of new snow. Light to moderate southwest winds. Alpine temperatures of around -11.Tuesday: Mainly cloudy with isolated flurries and a trace of new snow. Light to moderate southwest winds. Alpine temperatures of -13.Wednesday: Cloudy with flurries bringing around 5 cm of new snow. Light to moderate southwest winds. Alpine temperatures of -12.

An early report from Sunday details a natural cornice release that triggered an underlying slab to Size 2.5. Although it remains uncertain, a deep persistent weak layer is suspected as the failure plane. This occurrence should remind backcountry users that a very real potential currently exists for storm slab avalanches to 'step down' to one of several deeply buried weak layers. This would likely result in a very large and destructive avalanche.Reports from Saturday include numerous storm slab and wind slab avalanche observations on all aspects, generally from Size 2-2.5, with a few larger and smaller examples. Natural triggers were well represented and a number of avalanches ran full path. Two notable reports showed avalanches running on the February 15 crust as well as gouging features lower in the slope to ground level. Crown fractures averaged around 40 cm in depth but at least one reached as deep as one metre.Looking forward, expect a decline in natural avalanche activity while the potential for human triggering at the full depth of our recent snow persists a few more days.

Just under a week of stormy weather has delivered a wide ranging 25-70 cm of new snow to the region, with the bulk of the new snow arriving over Friday night and blanketing localized pockets with up to 40 cm. The new snow has buried widely reported faceted surface snow as well as surface hoar reported at about 3mm on shaded aspects before the storm. Moderate to strong southerly winds accompanied the new snow, promoting the formation of touchy storm slabs at all elevations. Multiple reactive shears have recently been reported within this recent storm snow. Now roughly 40-90 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. This layer has produced easy results in recent snowpack tests and has proven especially reactive on steep solar aspects. Several deeper weak layers also remain a concern, including the February 3rd surface hoar layer (50-130 cm deep), and the mid-January surface hoar layer in the northern Purcells (about 130 cm deep). Basal facets may still be reactive in shallow, rocky start zones.