Avalanche Forecast

Moderate - Due to the number of field observations

FRIDAY NIGHT: A weak front passes overnight bringing 5-10 cm of snow, strong wind out of the southwest, freezing level dropping from 1400 to 800 m, alpine temperatures around -6 C.SATURDAY: Clearing throughout the day, strong wind out of the west, alpine high temperatures around -4 C.SUNDAY: Increasing cloud throughout the day, moderate to strong wind from the southwest, alpine high temperatures around -2 C.MONDAY: Light flurries, moderate to strong wind from the southwest, freezing level rising to 1900 m.

Widespread natural avalanche activity was reported on Thursday and Friday, primarily size 1-2 wind slab avalanches on east-facing lee terrain in the alpine. Some appear to have stepped down to the deep persistent weak layer near the bottom of the snowpack. Heavy triggers, including, explosives, also produced some large and very large deep persistent slab avalanches (size 2-3) that failed on the weak snow at the bottom of the snowpack. These avalanches were primarily on north and east aspects and ranged in depth from 50-120 cm. On Thursday, the storm snow was also very reactive to skier and snowmobilie traffic, producing widespread cracking, whumpfing, and some small avalanches.See some photos of avalanche activity north of Crowsnest Pass from out field team's MIN report here.

About 20-30 cm of new snow has buried previous snow surfaces that ranged from soft power to hard wind slab and sun crust. Strong winds have likely been aggressively forming storm slabs and wind slabs with the new snow at higher elevations.Beneath the new snow and old surface, the snowpack has a thin, weak structure, with the bottom half of the snowpack composed of weak facets and crusts. This basal layer has not been active, but terrain features like smooth alpine bowls with variable snowpack depths are still suspect given this snowpack structure.Currently only 30-90 cm of snow can be found in alpine areas and much less at lower elevations.