Avalanche Forecast

Moderate - Forecast snowfall amounts are uncertain.

THURSDAY NIGHT: Cloudy with snowfall, accumulation 5 to 10 cm in the north of the region and 20 to 30 cm in the south, 40 km/h southwest wind, alpine temperature -6 C.

FRIDAY: Cloudy with snowfall then clearing, accumulation 5 to 10 cm, 30 km/h west wind, alpine temperature -8 C.

SATURDAY: Cloudy with snowfall, accumulation 5 cm, 30 km/h southwest wind, alpine temperature -11 C.

SUNDAY: Early-morning snowfall then clearing, accumulation 5 cm, 30 km/h southwest wind, alpine temperature -1 C, freezing level rising to 2100 m.

There was an observation of a large storm slab avalanche that was triggered naturally near Duffey Lake. The avalanche was suspected to have released at the base of the storm snow from January 1 and have occurred a few days ago.

Avalanche activity may increase on Friday as the result of Thursday night's storm.

Thursday night's storm is expected to deposit anywhere from 10 to 40 cm across the region, with the most in the south (e.g., Coquihalla, Manning). This snow may form new storm slabs in sheltered terrain features and wind slabs in lee terrain features from strong southwest wind. This snow builds on the 50+ cm of snow that has fallen since January 1, which may overly sugary faceted grains formed late-December. Reports suggest that this storm snow is bonding to the snowpack in much of the region.

Around 80 to 200 cm deep, a weak layer of faceted grains may be found above a melt-freeze crust that formed in early December. The layer is most prominent between 1700 and 2100 m. The last observed avalanche on this layer was around December 24, suggesting that this layer has become dormant. The most likely place to trigger it would be in thin, rocky snowpack areas.

The lower snowpack is well-settled and strong.

• Continue to make conservative terrain choices while the storm snow settles and stabilizes.
• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Make observations and assess conditions continually as you travel.
• Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.