Avalanche Forecast

Thursday night: Clear. Light east or northeast winds.

Friday: Sunny with light flurries developing overnight. Light east or northeast winds. Alpine high temperatures around -15.

Saturday: Cloudy with continuing scattered flurries bringing 5-10 total cm of new snow, easing in the afternoon and beginning again overnight. Light south winds. Alpine high temperatures around -11.

Sunday: Cloudy with flurries bringing another 5-10 cm of new snow and 2-day totals to 10-20cm, continuing overnight. Alpine high temperatures around -8.

With cold temperatures gradually robbing the upper snowpack of cohesion, observations from the past few days show a trend away from wind slab releases and toward small loose dry avalanches triggering in steep start zones with skier traffic. That said, a few more small wind slabs were still able to be triggered with ski cutting in the Whistler area on Tuesday.

Notably, a size 3 (very large) persistent slab was remotely triggered (from a distance) by a group of skiers in the McGillivray Pass area (northern South Coast Inland region) on Monday. This occurred on a southwest aspect at 2400 metres. It was described as a hard wind slab formed over the facet layer from late January detailed in our snowpack discussion.

Up to 15 cm of low density snow can be found on the surface in shaded, sheltered areas. In more wind exposed areas this is replaced with a mix of wind-affected surfaces, including wind slabs that are gradually losing cohesion and reactivity under prolonged cold temperatures. A thin recent sun crust may be found right near the surface on solar aspects.

Below this mixed bag of surface conditions, 50-100 cm of settled storm snow sits on a persistent weak layer from late January that consists of facets at upper elevations, surface hoar in sheltered areas, a melt-freeze crust below 1900 m, and a sun crust on south-facing slopes. There could be more than 100 cm on this layer in wind loaded areas. Although this structure is a bit suspect, we have no recent reports of avalanches failing at this interface within the region.

A crust from early December, currently considered dormant, may be found around 200+ cm deep in the snowpack.

• Carefully evaluate steep lines for wind slabs.
• Be aware of highly variable recent wind loading patterns.
• Pay attention to cornices and give them a wide berth when traveling on or below ridges.