Heightened avalanche conditions exist on wind-loaded terrain features where a cohesive slab has formed over a crust. Evaluate snow and terrain carefully.
Watch for pockets of fresh wind slab in atypical terrain features (think southwest aspects instead of northeast). Older wind slabs may remain triggerable where they sit over facets on a crust.
On Tuesday, our field team observed a natural size 2 slab avalanche on a north aspect at 1100m. The slab was 20-30 cm deep and failed on the facets above the crust.
If you head out in the mountains, please consider sharing your observations on the Mountain Information Network.
20 to 30 cm of facetted snow sits over a crust. In the Powder Valley, surface hoar was observed sitting over the crust in a recent MIN report.
Despite the presence of faceted grains in the lower snowpack, there are no layers of concern below the crust. Snowpack depths range from about 70 to 180 cm.
Tuesday night
Clear. 30 to 50 km/h east winds. Mild inversion developing; treeline temperature -15 °C.
Wednesday
Sunny. 40 to 60 km/h east winds. Inversion; alpine temperature -10°C, valley bottom -20 °C.
Thursday
Sunny. Outflows easing 40 to 20 km/h. Inversion; alpine temperature -12°C, valley bottom -23 °C.
Friday
Mostly sunny. 10 to 30 km/h southwest ridgetop wind. Inversion; alpine temperature -15°C, valley bottom -25 °C.
More details can be found in the Mountain Weather Forecast.
