Reactive wind slabs are most prevalent in immediate lee features at and above Tree-line. Flurries and winds associated with their passing will continue to promote their build-up.
Santa's little helpers know that the best skiing, and it is pretty darn good right now, is on slopes sheltered from these winds.
Steady, light snowfall this past week has left plenty of snow available for transport. Moderate/strong gusty winds will continue to refresh these slabs. This avalanche problem will be most reactive in the alpine and exposed areas at tree line.
Continuing flurries with blustery ridge-top winds
Tonight Isolated flurries, trace amounts, Alp low -8°C, South winds 15-30 km/h, freezing level (FZL) 900m.
Thurs Flurries, 5-10 cm, Alp High -4°C, winds light S gusting 40km/h, FZL 1500m.
Fri Sun/cloud/flurries, trace snow, Alp High -7°C, light wind gusting 30km/h, FZL 1000m.
Sat Flurries, 10-15cm, Alp High -5°C, light SW winds gusting to 40km/h, FZL 1200m
A natural avalanche cycle on Tues was observed in the hwy corridor off Mt Macdonald's N aspect. Wind spikes and the resulting snow transport were the likely triggers.
Reactive wind slabs were noted at both Teddy Bear Trees and McGill Tues pm.
On Monday, several small, sz 1 skier-controlled avalanches from steep, unsupported rolls were noted on Perley Rock around 1900-2000m.
Continuous snowfall the past week has brought 90+cm. Mod to strong S/SW winds formed a reactive wind slab in specific features (ridge lee areas, open cross-loaded slopes, convex rolls).
Sheltered slopes hold excellent skiing.
A persistent weak layer is down 90-120cm. This interface is breaking down, but consists of surface hoar in sheltered locations, and a sun crust on solar aspects. The snowpack's base is comprised of several early-season melt-freeze rain crusts
