Watch for wind slabs in atypical terrain features at upper elevations. Be wary of thin or rocky start zones where wind slabs may trigger easily over weak grains or a slippery crust.
Watch for wind slabs on a variety of aspects including reverse-loaded terrain features at upper elevations. Be wary of thin or rocky start zones where wind slabs may sit over weak facets or a slippery crust.
This MIN from near Duffey Lake on Friday describes shooting cracks and small natural and skier-triggered wind slab avalanches on west aspect in the alpine
Low density surface snow has likely seen some redistribution by moderate east to southwest winds at upper elevations.
The upper and mid snowpack are generally faceted with a couple of crusts in the top meter. The thin upper crust extends up to 1900 m and is most prominent on solar aspects. The second crust is buried 60 to 100 cm deep and may have a layer of surface hoar sitting above it. There is uncertainty over its reactivity. It is more likely to be a concern in wind-affected, thin, and rocky start zones at higher elevations.
Snow depths at treeline are roughly 100 to 150 cm.
Saturday night
Cloudy with 2 to 8 cm of snow. Southwest ridgetop wind increasing 10 to 30 km/h. Treeline temperature -6 °C.
Sunday
A mix of sun and cloud. 10 to 20 km/h southwest ridgetop wind. Treeline temperature -5 °C.
Monday
Sunny. 10 to 20 km/h northeast ridgetop wind. Treeline temperature -3 °C.
Tuesday
A mix of sun and cloud. 20 to 40 km/h southwest ridgetop wind. Treeline temperature 0 °C. Above freezing layer developing 2000 to 2700 m.
More details can be found in the Mountain Weather Forecast.
