Dogtooth

Uncertainty about buried weak layers warrants conservative terrain choices.

Deep persistent slab avalanches (size 1.5 to 2) have been continually triggered with explosive control over the past week, with the most recent occurrence on Monday. On Sunday, a skier in the Dogtooth Range was uninjured after accidentally triggering a size 2 deep persistent slab on basal facets over a smooth rock slab.

New snow is (very) gradually accumulating over surface hoar, facets, and crusts. Beneath lies a thin and complex snowpack with several layers of concern:

• A layer of surface hoar buried 20 to 50 cm deep is a concern in areas where it is not covered by a thick crust.

• Weak basal facets near the bottom of the snowpack, especially in alpine terrain.

Read this blog post for more details.

Snowpack depths at treeline range from 50 to 130 cm.

Thursday night

Mostly cloudy with a trace of snow, alpine wind southwest 20 km/h, treeline temperature -10 °C.

Friday

Mostly cloudy, alpine wind west 20 km/h, treeline temperature -6 °C.

Saturday

Cloudy with 3 to 8 cm of snow, alpine wind southwest 10 km/h, treeline temperature -6 °C.

Sunday

Sunny, alpine wind southwest 15 km/h, treeline temperature -10 °C.

More details can be found in the Mountain Weather Forecast.

• Uncertainty is best managed through conservative terrain choices at this time.
• Be mindful that deep instabilities are still present and have produced recent large avalanches.
• Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.