Avalanche Forecast

Good

A series of frontal systems will be sending waves of moderate precipitation amounts accompanied by strong to extreme winds through the forecast period. Model runs are in agreement with timing and precipitation amounts. Snow amounts are significantly less in the Northern parts of the region.Sunday night: Snow amounts 25 cm. Ridgetop winds blowing light from the SW gusting strong. Monday: Snow amounts 10-15 cm. Alpine temperatures -4.0. Light SW ridgetop winds with strong gusts.Tuesday: Snow 15-20 cm ramping up in the afternoon. Alpine temperatures near -2.0. Ridgetop winds light from the SW gusting strong. Wednesday: Light snow. Alpine temperatures near -6.0 with light SW ridgetop winds.

On Saturday skiers recreating in the Coquihalla area triggered a size 2 slab avalanche on a steep slope in open trees, below treeline. One partial burial occurred, sustaining some injury. One natural cornice release triggered a size 2.5 slab avalanche on the slope below and explosives control produced numerous 2.5-3.5 avalanches. All elevations and aspects continue to have a storm slab problem that will likely persist through the next several days and the avalanche danger will remain high.

The Northern parts of the region have recently received up to 90 cm of new storm snow and the Southern areas have seen anywhere up to 140 cm with more forecast. This new storm snow overlies a variety of old surfaces consisting of facets, surface hoar, a scoured crust, wind press, or any combination of these. Particularly of concern is the combination of buried facets on a crust being unusually reactive at treeline and below treeline elevations. Whumpfing and widespread avalanche activity further indicate a poor bond between the new snow and these old surfaces.Strong to extreme winds are shifting the new snow into deeper, reactive wind slabs in leeward terrain.The mid and lower snowpack are generally strong and well-settled. Although basal facets and depth hoar are likely to exist in the north of the region.