West Purcell

New snow and wind will create dangerous avalanche conditions.

The Forecaster Blog explains how to manage the changing conditions.

A few size 1 wind slab and loose dry avalanches have been reported since Tuesday, along with some loose wet avalanches from steep south aspects.

We expect to see an increase in avalanche frequency and size as the new snow amounts increase.

The new snow has fallen on a variety of old surfaces. There is surface hoar, most prevalent at treeline and below treeline elevations, a crust on sun-facing slopes, and 20 to 30 cm of low-density faceted snow in sheltered areas.

Dry January conditions have created a weak, faceted upper snowpack with multiple surface hoar and crust layers. These layers are a concern with the new snow amounts forecasted.

The mid and lower snowpack remains generally well-settled and strong, with no current concerns or significant instability noted.

Friday night

Cloudy with 10 to 20 cm of snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -7 °C.

Saturday

Scattered cloud with 5 to 10 cm of snow. 20 to 30 km/h west ridgetop wind. Treeline temperature -11 °C.

Sunday

Mostly cloudy with 5 to 10 cm of snow. 10 to 20 km/h south ridgetop winds. Treeline temperature -12 °C.

Monday:

Mostly cloudy with 0 to 5 cm of snow. 10 to 20 km/h southeast ridgetop wind. Treeline temperature -14 °C.

More details can be found in the Mountain Weather Forecast.

• Storm slab size and sensitivity to triggering will likely increase through the day.
• Be aware of the potential for larger than expected storm slabs due to buried surface hoar.
• Loose avalanches may start small, but they can grow and push you into dangerous terrain.