Northwest Coastal

Avalanche danger is expected to increase and natural avalanches are likely in response to heavy loading from snow and wind.

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Another storm is expected to roll in Tuesday morning with the main pulse of snow coming Tuesday afternoon bringing as much as 20-25 cm by Wednesday afternoon. Ridgetop winds are expected to be strong to extreme initially from the south before shifting to southwesterlies and easing off slightly be Wednesday evening. Freezing levels could briefly rise to 1000 m in coastal areas midday Tuesday, but generally remain at valley bottoms further inland. Another even stronger storm is expected to arrive late Thursday.

Skiers in the Shames area reported natural and skier accidental avalanche activity up to size 1.5, and skier controlled up to size 2.0 on Friday, but there have been no new reports since then. These avalanches are suspected to have released on a buried layer of decomposing surface hoar that is sitting on a firm supportive crust down about 50-80 cm in the alpine.

Coastal areas got around 50 cm of fresh snow throughout Sunday into Monday morning, but the storm dried out as it progressed inland with around 20 cm at Shames. Recent reports from the Shames area suggest a touchy weak layer of surface hoar buried mid-November and is now probably down about 50-80 cm and sitting on a firm supportive crust, making it particularly sensitive to triggers. Some earlier information came from Wesach that suggested the buried surface hoar problem exists there as well. This weak layer has been reactive to light loads like individual skiers and riders. There is very little snow in the north of the region at Ningunsaw and Cassiar. Snow that is on the ground in these areas may be facetting and developing a weak basal layer.