Avalanche Forecast

Moderate -

Unsettled conditions are expected to continue on Tuesday with sunny breaks in the morning and light snowfall in the afternoon. 5-10 cm of snowfall is forecast between Tuesday afternoon and Wednesday morning. Alpine wind is expected to be moderate to strong from the southwest and treeline temperatures are forecast to be around -10C. Unsettled conditions are expected again on Wednesday with the potential for both sunny breaks and light flurries. Alpine wind is forecast to be moderate from the southwest and treeline temperatures should remain around -10C. There is currently a lot of uncertainty for Thursday but it looks like a storm system could arrive in the afternoon or overnight.

On Sunday, a natural size 2 avalanche was observed on a southerly aspect in the Duffey area. Whumphing and cracking on open southerly aspects below treeline was also reported on Sunday in the Duffey area. On Saturday, natural avalanches were reported up to size 2.5 from the north of the region on NE facing slopes between 1900 and 2450m. On Friday overnight, a natural cycle released avalanches up to size 4 in the Coquihalla area. These avalanches were failing on facets above a crust, with the crust allowing debris to run fast and far. On Saturday in the Coquihalla, a couple of sleds were buried in what looks to be a size 2 avalanche at treeline. Click here for more details.On Tuesday, strong southwest wind is expected to develop touchy new wind slabs and thicker old wind slabs may also still be reactive. The weak layers from February are still a major concern and persistent slab avalanches remain possible. It may still be possible for a person to directly trigger a persistent slab or a smaller avalanche could step down. We are entering a low probability, high consequence scenario for very large persistent slab avalanches.

10-20 cm of new snow on Sunday brings the typical storm total to 40-70 cm since last Wednesday in the north of the region and to over 1 m in the south of the region. Strong south and southwest wind during the storm redistributed much of this snow in wind-exposed terrain forming thick wind slabs. The new snow overlies the mid-February and late-February interfaces which may be close together in the snowpack. The late-February interface consists of wind affected surfaces in exposed terrain, sun crust on steep solar aspects, and up to 20cm of facets in sheltered areas. The mid-February interface consists of a thick rain crust which extends to at least treeline, a sun crust on steep solar aspects, and in many places, a layer of facets overlying the crust. Recent observations suggest the late-February layer is most reactive in the north of region and the mid-February layer is most reactive in the south of the region. Below these layers, the mid and lower snowpack are generally well settled and strong.