Avalanche Forecast

Moderate - Forecast snowfall amounts are uncertain.

Light snow and flurries will continue in most areas as a cold northeasterly flow begins to assert itself at the surface. This will bring persistent cloudiness and continued light snowfall amounts through the Christmas weekend.

Thursday Night: New snow 5-10 cm accompanied by moderate southwest wind. Treeline temperatures -8 and freezing level at the valley bottom.

Friday: New snow 5-10 cm with strong southerly winds. Treeline temperatures near -10 and freezing levels near 800 m. Temperatures continue to drop overnight.

Saturday: Cloudy with 5-15 cm accompanied by moderate southwest wind. Treeline temperatures near -15 and freezing levels at the valley bottom.

Sunday: Cloudy with some flurries up to 5 cm. Light winds from the southwest and colder temperatures at -15. 

On Thursday, numerous storm slabs were triggered by machines and explosives. The majority of them were size 2 with one size 3 reported. 

Natural avalanche activity may taper on Friday but slab avalanches likely remain primed for human triggering.

30 to 50 cm of recent storm snow sits above a surface hoar interface and pockets of old wind slab. Low-density storm snow exists in wind-sheltered sheltered terrain.

Below the new snow exists a well-consolidated upper snowpack which overlies a substantial crust that formed in early December. This crust is approximately 90-150 cm below the surface, 20 cm thick on average, and is present across all aspects to at least 2400 m. A layer of weak facets (sugary snow) has been reported above this crust. Snowpack tests are generally showing hard results on this interface.

The lower snowpack consists of a variety of early-season crusts and mainly moist snow. Snowpack depths range from 100-200 cm at treeline elevations and taper quickly below 1800 m.

• Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
• Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
• Start with conservative lines and watch for clues of instability.
• Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.