Purcells

Cooling temperatures are reducing the likelihood of triggering large persistent slab avalanches.

Avoid steep or convex terrain features with a shallow or thin-to-thick snowpack.

Naturally triggered wet loose avalanches up to size 2.5 were reported on sunny aspects at all elevations on Wednesday.

0 to 5 cm of new snow overlies predominantly crusty surfaces.

A widespread, hard crust down 40 - 110 cm with weak facets above continues to be the primary layer of concern for human triggering of very large persistent slab avalanches.

The bottom of the snowpack is generally weak and faceted, with the potential to produce very large avalanches. The most likely areas to trigger this deeply buried weak layer are steep, rocky areas in the alpine with a shallow or thin to thick snowpack.

Thursday night

Mostly cloudy. 10 to 20 km/h west ridgetop wind. Treeline temperature -7 °C. Freezing level valley bottom.

Friday

Mix of sun and cloud. 10 to 20 km/h west ridgetop wind. Treeline temperature -4 °C. Freezing level 1600 m.

Saturday

Cloudy. 10 to 20 km/h southeast ridgetop wind. Treeline temperature -5 °C. Freezing level 1300 m.

Sunday

Mostly cloudy. 10 to 20 km/h east ridgetop wind. Treeline temperature -9 °C. Freezing level 900 m.

More details can be found in the Mountain Weather Forecast.

• Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
• When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
• Conditions may have improved, but be mindful that deep instabilities are still present.
• Cornice failure may trigger large avalanches.