A powerful storm will impact the region, forming new slabs and loading buried weak layers. Conservative terrain travel will be key as well as avoiding avalanche terrain during periods of rapid loading and/or if you find more than 30 cm of snow accumulation.
Numerous weak layers may exist in the top half of the snowpack, including surface hoar and faceted grains over a melt-freeze crust. These layers were recently triggered in riding areas north of Terrace and the likelihood of avalanches on these layers will increase during this stormy period.
Upwards of 40 cm of snow may accumulate in the region by Friday afternoon, with the most snow expected in the west of the region. Storm and wind slabs will build rapidly and they will load buried weak layers. An avalanche cycle may occur at some point during the next few days.
THURSDAY NIGHT: Cloudy with snowfall, accumulation 10 to 20 cm with the most along the west of the region, 60 km/h southwest wind, alpine temperature -3 C, freezing level 900 m.
FRIDAY: Cloudy with snowfall, accumulation 10 to 20 cm with the most along the west of the region, 40 to 60 km/h southwest wind, alpine temperature -2 C, freezing level 1000 m.
SATURDAY: Cloudy with snowfall, accumulation 20 to 40 cm, 60 km/h southwest wind, alpine temperature -5 C.
SUNDAY: Cloudy with snowfall, accumulation 5 to 10 cm, 40 km/h southwest wind, alpine temperature -6 C.
An avalanche cycle may occur at some point in the coming days, once sufficient snow loads the buried weak layers described in the snowpack summary. Avalanches could be triggered naturally or by riders and the result may be very destructive.
A hefty storm is forecast to impact the region for the coming days. Up to 40 cm of snow may accumulate by Friday afternoon, particularly along the western side of the region. The snow will come with strong southwest wind, which will rapidly form wind slabs in exposed terrain. All of this snow will load a layer of surface hoar that was buried 10 to 20 cm prior to this storm. The surface hoar was reported as being widespread prior to burial and it may sit on a melt-freeze crust from warm air on Boxing Day and/or from sunny skies.
Another weak layer surface hoar may be found around 30 to 60 cm deep. The most likely places to find this layer would be in terrain features sheltered from wind effect.
Around 100 to 200 cm deep, a hard melt-freeze crust from early December may have weak and sugary faceted grains around it. These weak layers are likely the culprit of recent avalanche activity in the Nass Valley, Sterling, and Beaupre riding areas.
The early-November melt-freeze crust is over 200 cm deep and may have faceted grains above it in parts of the region, particularly in the north. The last reported avalanche activity was near Ningunsaw on December 11.
