A complex snowpack has led to several recent avalanche incidents, including a fatal avalanche near Pemberton. Clues of instability may not be obvious, so stick to low-angle terrain at all elevations and avoid overhead hazard.
Wind loaded pockets below ridge crests and rollovers may be reactive to human triggers. Watch for localized reverse-loading on south-facing slopes due to recent northerly winds.
Weak layers of surface hoar and/or faceted grains may be found above a melt-freeze crust. Recent reports suggest this weak layer may be less prevalent in the south of the region, but still exists in localized pockets.
WEDNESDAY NIGHT - Flurries, up to 5 cm / southwest wind, 20-40 km/h / alpine low temperature near -5
THURSDAY - Mainly cloudy / light west wind / alpine high temperature near -5
FRIDAY - Flurries, 5-10 cm / southwest wind 40-60 km/h / alpine high temperature near -2 / freezing level 1400 m
SATURDAY - Flurries, 5-10 cm / southwest wind, 40-60 km/h / alpine high temperature near -2 / freezing level 1400 m
There was a fatal avalanche north of Pemberton in the Railroad Pass area on Monday that resulted in two fatalities. It was reported to be a size 2 persistent slab avalanche on a west aspect, around 1650 m. The RCMP press release can be viewed here and the Avalanche Canada report can be found here.
A size 2 avalanche was triggered on Monday by a skier on a northwest aspect in the alpine on Mt. Matier (Duffey). The avalanche occurred on a northwest aspect and was likely a wind slab avalanche. It carried the skier over cliffs resulting in several injuries. A MIN report detailing this incident can be found here.
Numerous smaller (size 1) skier triggered avalanches were also reported around the Duffey on Monday.
A size 1 wind slab avalanche was reported on an east aspect on Cayoosh on Sunday. Storm slabs and loose dry avalanches were also reported from Chief Pascal on the Duffey and on the Yak/Nak col along the Coquihalla.
A few persistent slab avalanches were reported last week, mostly in the north of the region near the Hurley, but also near Allison Pass. They were triggered by riders, heavy machinery, and naturally. The slabs were generally 60 to 90 cm deep, around 2000 m, and released on the weak layers described in the snowpack summary.
15-25 cm of recent snow has seen some redistribution by wind, likely resulting in fresh wind slab formation. Below treeline, the recent snow may be sitting over surface hoar.
A melt-freeze crust from early December is found around 40 to 120 cm deep in the snowpack. This crust may have feathery surface hoar or sugary faceted grains sitting above it. This persistent weak layer is most prevalent in the north (e.g., Duffey Lake, Hurley) and found to a lesser extent in the south of the region.
The remainder of the snowpack is generally well settled in the south of the region. In the north, another melt-freeze crust with faceted grains around it may be found near the ground. This layer has not produced any recent avalanches.
