Watch for hard wind slabs in exposed alpine areas. Start with small features before moving into bigger terrain.
Reports of wind slab avalanche activity are decreasing however where wind slabs overlie a weak layer of facets or surface hoar they may remain reactive to human triggering.
On Wednesday, several, size 1 and size 2 loose wet and glide slab avalanches were reported triggered by warm temperatures and solar input. As temperatures cool Wednesday night avalanche activity is expected to subside.
On Tuesday, a size 1.5 skier-triggered wind slab avalanche was reported on a north aspect at 1900 m. The wind slab released on a weak layer of surface hoar found below.
At 2200 m and below, the moist snow surface is refreezing into a thick crust. In the alpine and exposed treeline, this crust overlies old wind slabs and wind-affected surfaces. On sheltered northerly aspects in the alpine, dry snow may exist.
10 to 30 cm down is a small weak layer of surface hoar or facets. This layer remains a concern in isolated areas where a wind slab overlies it.
A crust is buried 60 to 100 cm deep and may have a layer of surface hoar sitting above it. Recent tests show this layer as unreactive.
The remainder of the mid and lower snowpack is well-settled.
Snow depths at treeline are roughly 100 to 150 cm.
Wednesday Night
Increasing cloud. 35 to 45 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing levels drop to 1000 m.
Thursday
Mostly cloudy with light flurries, 1 cm. 10 to 25 km/h northwest ridgetop wind. Treeline temperature -5 °C. Freezing levels drop to the valley bottom.
Friday
Mainly sunny. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -9 °C.
Saturday
Partly cloudy. 5 to 10 km/h west ridgetop wind. Treeline temperature -10 °C.
More details can be found in the Mountain Weather Forecast.
