Avoid aggressive terrain choices where a persistent slab problem could exist. Steep, rocky, shallow terrain are the most likely trigger areas.
Wind slabs formed over the weekend are becoming more difficult to trigger but may be reactive where they overlie surface hoar or a melt-freeze crust.
The early December weak layer remains a concern in areas with a shallow snowpack, particularly on steep rocky slopes.
Two notable avalanches occurred in the Dogtooth Range on Saturday:
A skier was caught in a size 2.5 wind slab avalanche that propagated widely across a northeast-facing slope. It ran on a 5 to 40 cm deep surface hoar layer. See this MIN report for details.
A group of skiers remotely triggered a size 2.5 persistent slab avalanche on a large southwest-facing alpine slope.
Many smaller (size 1 to 1.5) wind slab avalanches were also reported across the Purcells.
Surface snow is a mix of newly developed surface hoar and sun crust. Wind-loaded pockets exist above various layers of soft snow, surface hoar, and melt-freeze crust.
A weak layer of facets buried in early December is on average 60 to 90 cm deep (except closer to 30 cm in the shallower eastern parts of the Purcells). This layer continues to cause occasional large avalanches.
The snowpack base consists of a thick crust and facets in many areas.
Tuesday Night
Partly cloudy. 10 km/h west ridgetop wind. Treeline temperature -5 °C.
Wednesday
Partly cloudy. 10 km/h southwest ridgetop wind. Treeline temperature -4 °C.
Thursday
Partly cloudy. Isolated flurries,1 cm. 40 km/h southwest ridgetop wind. Treeline temperature -5 °C.
Friday
Partly cloudy. Isolated flurries 1 to 2 cm. 30 km/h northwest ridgetop wind. Treeline temperature -5 °C.
More details can be found in the Mountain Weather Forecast.
