Avalanche Forecast

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The arctic air has set in the North bringing some of the lowest temperatures of the season. The next change in the weather pattern looks to come Thursday afternoon as the next pacific frontal system tracks onto the south coast. The battle between the cold arctic air and the warm pacific air will bring cloudy unsettled conditions. Track and timing will play a huge role and mostly affect the south,.Tuesday/ Wednesday: Sunny with some cloudy periods. Alpine inversions will exist with temperatures near -19 up high and -25 in the valley. Ridgetop winds will blow moderate strong from the east.Thursday: Mostly cloudy with nil precipitation. Alpine temperatures -16 and moderate ridgetop winds from the east.

Check out the new MIN report for the Miller Ck/ Crater Lk area. That report indicated a natural size 2 slab avalanche which appeared to be a cornice failure in steep complex terrain. The avalanche was noted from a southeast aspect at 1850. The crown was 20-30 cm thick, 60 m wide and running up to 300 m in length. Watch for the development of wind slabs on all aspects as the current winds are switching from the SW and blowing from the NW. Slopes and terrain features could become reverse loaded and catch you by surprise. Cracking, whumphing and natural avalanche activity are indicators of unstable snow.

New snow combined with strong winds from the southwest have likely formed touchy wind slabs on lee features. Forecast switching winds from the northeast may reverse load slopes and catch you by surprise. A layer of surface hoar was reported around Hudson Bay Mountain last week, which now sits beneath 40-50 cm of settling snow. A thick rain crust that formed in early November is now buried 50-60 cm deep, and recent snowpack tests produced sudden results on facets (sugary snow) above this crust. Early season snowpack observations are still very limited in the region, but reports suggest the average snowpack depth is 50-90 cm at treeline and 120 cm or greater in the alpine.