Purcells

Remain cautious in high-consequence terrain.

Wind slabs may be reactive to human triggering in the alpine.

On Thursday, a small naturally triggered wind slab occurred near Panorama and a skier triggered a large (size 2) loose dry avalanche in the Esplanades.

On Wednesday, a small remotely triggered wind slab occurred on a southwest alpine slope. Explosives triggered large cornices which then triggered a slab below. Whumpfing and shooting cracks were observed here.

Looking forward, we expect human triggering of small wind slabs and loose dry avalanches to remain possible.

Exposed terrain in the alpine and treeline is generally wind-affected. In sheltered terrain, 10 to 40 cm of faceted snow overlies a weak layer from late January. This layer consists of a crust on sun-exposed slopes and surface hoar on all other aspects. A weak layer of facets from early December is buried 60 to 120 cm. The base of the snowpack consists of a thick crust with facets or depth hoar in many areas.

Friday Night

Mostly cloudy with isolated flurries. 5 to 10 km/h west ridgetop wind. Treeline temperature -14 °C.

Saturday

A mix of sun and cloud. 5 to 10 km/h west ridgetop wind. Treeline temperature -14 °C.

Sunday

Mostly cloudy with isolated flurries. 15 km/h southeast ridgetop wind. Treeline temperature -13 °C.

Monday

A mix of sun and cloud. 5 to 10 km/h north ridgetop wind. Treeline temperature -10 °C.

More details can be found in the Mountain Weather Forecast.

• Pay attention to isolated wind affected features in the alpine, as well as cross-loaded features at treeline.
• Use caution above cliffs and terrain traps where even small avalanches may have severe consequences.
• Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.