Wind slabs are the primary concern and may be reactive to rider triggers. In shallow snowpack areas wind slabs could step down to deeper weak layers initiating a large and destructive avalanche.
Summary
Confidence
High - The weather pattern is stable
Weather Forecast
Thursday: Sunny with alpine temperatures near -10. Ridgetop winds light from the southeast. Friday: Snow amounts 5-10 cm with alpine temperatures near -5. Ridgetop winds light from southwest. Saturday: Snow amounts 5-15 cm with alpine temperatures near -3. Freezing levels 1200 m and ridgetop winds light-gusting strong from the southwest.
Avalanche Summary
On Tuesday no new avalanches were reported from the region. Expect wind slabs to linger on lee and crossloaded features at higher elevations.
Snowpack Summary
In exposed areas at treeline and in the alpine, the surface snow consists of stiff wind slab or wind effected snow. Adding to the mix you may see sun crust on steep southerly slopes and surface hoar. Below the surface, 50-65 cm of settled snow now sits above an interface that was buried in mid-January. The interface is composed of facets, surface hoar, and/or sun crusts and the strength is reportedly variable. Recent snowpack tests have shown sudden results on that interface. Areas with thin snowpacks (e.g. less than 150 cm) have a generally weak snowpack structure with sugary facets near the ground. This includes shallow alpine slopes and most of the Rossland range. These deeper weaknesses warrant monitoring and create a complicating picture. It may be a low probability that you would trigger an avalanche that failed on these basal facets, however; the consequences could be detrimental. This makes for tricky especially decision making. These layers may be unreactive or even sit dormant now with this stable weather pattern but they could reawaken with a change.
swerner,
Avalanche Canada
