North Columbia

As the storm continues, keep in mind that the hazard will increase in areas experiencing heavy snowfall, warm temperatures and high winds. Conservative terrain selection and minimizing overhead hazard is recommended.

Moderate - Forecast snowfall amounts are uncertain

Forecast snowfall amounts vary greatly throughout the North Columbia, with the highest amounts predicted in the Monashees. MONDAY NIGHT - Snow, 5-15 cm / moderate southerly winds / freezing level 1200 metresTUESDAY - Snow, 10-15 cm / moderate southerly winds / freezing level 1400-1800 metresWEDNESDAY - Cloudy with flurries, up to 5 cm / light to moderate southwest winds / freezing level 1300-1500 metresTHURSDAY - Cloudy with sunny periods and isolated flurries, up to 5 cm / light to moderate southwest winds / freezing level 1200 metres

One natural storm slab avalanche was reported on a northwest aspect at 2700 m on Sunday.Several size 1 rider triggered storm slab avalanches were reported on Monday afternoon.Of note, a size 3 human triggered avalanche that likely ran on the October crust was reported on Saturday, November 24 in the South Columbia region. The avalanche reportedly occurred on a northwest aspect, on a lee feature in the alpine. The full report can be found on the Mountain Information network. Click here to read the report

Ongoing snowfall since Sunday night brings total recent storm snow amounts to anywhere from 30-70 cm by Tuesday morning. As the snow is forecast to continue throughout the day, total accumulations could reach 40-85 cm by Tuesday evening. This new snow sits on top of a weak layer of surface hoar (feathery crystals) and sun crust on steep south facing slopes. The surface hoar is most pronounced at treeline and below, but it may be found in wind sheltered alpine areas.At the base of the snowpack is a crust that formed in late October. There have been no reports of reactivity on this layer in the North Columbia region, however with additional snow, strong winds and rising freezing levels, this layer could come into play during this storm. Storm slab avalanches may have the potential to trigger avalanches on this deeper layer.Total snowpack depths vary greatly with elevation. Recent reports show depths of 120-210cm in the alpine, 80-150 cm at treeline and 10-120 cm below treeline.