North Columbia

It's all about the new snow right now. In the alpine, it's been blown into thick and reactive wind slabs. At mid and lower elevations, thinner but more widespread slabs have been releasing over a weak layer of surface hoar.

High -

Sunday night: Cloudy with clear periods. Light northwest winds.Monday: Cloudy with sunny periods. Light northwest winds increasing and shifting to southwest in the evening. Alpine high temperatures around- 12.Tuesday: Mainly cloudy with scattered flurries bringing around 2 cm of new snow., continuing overnight. Light to moderate southwest winds. Alpine high temperatures around -6.Wednesday: Cloudy with continuing flurries and another roughly 2-5 cm of new snow, ending in the afternoon. Light west winds. Alpine high temperatures around -6.

Sunday was a busy day for avalanches running on the newly buried weak layer below our new snow. Numerous small storm slabs were observed releasing naturally, with remote (from a distance) triggers, and with skier traffic and ski cutting throughout the North Columbias as well as in neighbouring regions.Storm slabs were especially reactive, although usually quite thin (15-20 cm), from about 1500 to 1800 metres, where surface hoar is most prevalent. In the alpine, where surface hoar is less well preserved, quite a few larger (size 2), deeper wind slabs released with similar triggers. These were focused on northeast slopes to the lee of recent moderate to strong winds.Slab avalanches are currently most likely in wind affected terrain and at mid elevations where our surface hoar is best preserved. The key is watching for signs of the new snow becoming reactive, such as cracking, whumpfing, or stiffer, deeper pockets of snow.

15-25 cm of new snow from the weekend now sits above a layer of large surface hoar crystals and sun crusts. The new snow has been settling into a thin but reactive slab above this weak layer, with enhanced reactivity noted at elevations between about 1500-1800 metres, where surface hoar is particularly well developed. Although the surface hoar is less prevalent in the alpine, strong southerly winds during and immediately after the storm formed deeper and similarly reactive deposits on lee slopes at higher elevations. New snow deposits that overlie sun crust on steep, south-facing slopes may be especially touchy. The middle and lower portions of the snowpack are generally well-settled and strong.