North Columbia

Be cautious as you transition into areas where the surface snow has slab properties.

Wind slabs remain reactive to human triggering.

On Friday, explosive avalanche control generally produced size 1 to 2 wind slabs, with one step down avalanche that was size 2.5 on a north aspect at treeline.

Multiple human triggered wind slabs in the alpine and treeline in variably wind affected terrain were reported on both Thursday and Friday. Many of these avalanches have been on west aspects.

30 to 50 cm of recent snow from the last two storms has buried a variety of snow surfaces. It sits above unconsolidated faceted snow, surface hoar and firm wind-pressed snow in open terrain at treeline and above.

Down 60 to 80 cm, a crust, facet and or surface hoar layer exists. This may become a problem once the snow above starts to stiffen and form a slab.

130+ cm down another surface hoar layer exists that was buried in early December. This layer is of most concern above 2000 m where a robust crust doesn't exist above it.

Weak basal facets are likely to be found on the ground in shallow snowpack areas.

Saturday Night

Cloudy with up to 3 cm of snow, alpine wind south 20-40 km/h, treeline temperature -5 C.

Sunday

Cloudy with up to 3 cm of snow, alpine wind south 10-30 km/h, treeline temperature -2 C.

Monday

Cloudy with up to 2 cm of snow, alpine wind south 10-30 km/h, treeline temperature 0 °C.

Tuesday

Cloudy with up to 5 cm of snow, alpine wind south 10-30 km/h, treeline temperature -8 °C.

More details can be found in the Mountain Weather Forecast.

• Be especially cautious as you transition into wind affected terrain.
• If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.