Choose terrain sheltered from the wind. Avalanche danger will increase at upper elevations throughout the day.
Wind slabs will become increasingly dangerous on lee terrain features throughout the day. This is due to extreme southwesterly wind and 5-15 cm of new snow. While fresh wind slabs will form on north and east facing slopes, older wind slabs may still be reactive on steep south-facing slopes as well.
A frontal system crossing the region over the weekend will bring moderate amounts of low density snow and very strong wind.
FRIDAY NIGHT: Increasing cloud with a trace of snow around Pine Pass, strong wind from the west with gusts to 70 km/h, treeline temperatures around -25 C.
SATURDAY: Cloudy with snowfall, 5-15 cm of low density snow with the greatest accumulations around Pine Pass, strong to extreme wind from the southwest with gusts exceeding 100 km/h, treeline temperatures reach -15 C.
SUNDAY: Cloudy with snowfall, 10 to 20 cm of low density snow, moderate wind from the south with gusts to 50 km/h, treeline temperatures around -25 C.
MONDAY: Mostly cloudy with isolated flurries and trace amounts of snow, strong wind from the east, treeline temperatures drop to -30 C.
No recent avalanches have been observed in the North Rockies.
We'd appreciate if you submit your observations to the Mountain Information Network, even just a photo.
This weekend's storm looks to bring anywhere from 10 to 40 cm of low density snow. Extreme southwest wind will have a dramatic impact in open terrain and form reactive wind slabs on lee slopes. Sheltered terrain should have very low density powder. The incoming snow will bury old wind affected surfaces and may bond poorly to the cold faceted snow that has been exposed to the cold temperatures over the past week.
A weak layer of feathery surface hoar may be found around 20 to 50 cm deep. It is most likely found in sheltered terrain features in the lower alpine and treeline, or open features below treeline (e.g., cut blocks). We've only received a few reports of this layer, so it may be spotty in the region.
The middle of the snowpack has been reported as well-settled and strong. The base of the snowpack is composed of weak faceted grains, particularly in thin snowpack areas east of the divide, but has not recently been a concern.
