North Columbia

The snowpack remains ripe for human triggering, with natural avalanches likely where snowfall and strong winds persist.

Avoid exposure to avalanche terrain.

As of Monday morning, an ongoing avalanche cycle is occuring from heavy snow, wind and rain. Avalanches are expected to fail on mid storm layers and buried weak layers, producing large avalanches as seen in the last storm cycle.

On Tuesday, we expect natural activity may be tapering off, but human triggering remains very likely.

By Tuesday afternoon, storm totals are expected to reach 40 to 85 cm. This adds to the 50-150 cm of rapidly settling snow from last week. Upper elevations are likely heavily wind affected, while treeline and below likely holds a surface crust from recent rain.

Reactive weak layers exist in the mid and lower snowpack, producing avalanches during the last 10 days of heavy snowfall.

• Surface hoar or facets sit below the recent storm snow.

• A crust from mid November sits 100-180 cm deep, with faceted snow above.

Monday Night
Mostly cloudy. Up to 30 cm overnight for the north and east of the region. 3 to 10 cm of snow elsewhere. 50 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1700 m.

Tuesday
Mostly cloudy. 2 to 5 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -6 °C. Freezing level 1300 m.

Wednesday
Mostly cloudy. 20 to 30 cm of snow. 40 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing level 1400 m.

Thursday
Mostly cloudy. 4 to 10 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -7 °C. Freezing level 300 m.

More details can be found in the Mountain Weather Forecast.

• Avoid avalanche terrain during periods of heavy loading from new snow, wind, or rain.
• Storm slabs in motion may step down to deeper layers resulting in large avalanches.
• Avoid shallow snowpack areas, rocky outcrops, and steep terrain where triggering is most likely.