Avalanche danger will drop as the temperature cools, however, a widespread melt-freeze crust will make for challenging riding.
Weather Forecast
Freezing levels will continue to drop as a cold front moves across the province. A ridge of high pressure will build over the coast Wednesday resulting in clear skies and light SW winds over the interior. A weak front will move across the province on Friday and may produce isolated flurries.
Avalanche Summary
As the temperature drops I expect that avalanche activity will slow down. The recent snow, rain, and wind were a great test of buried persistent weaknesses in the snowpack and resulted in a widespread avalanche cycle. The mid-January surface hoar layer has been responsible for the majority of the recent avalanches.
Snowpack Summary
I suspect that freezing levels rose as high as 3000m during the recent warm spell and that rain may have saturated the upper snowpack. At higher elevations the surface is heavily wind affected. A breakable crust already exists in the alpine and as the freezing level continue to drop a widespread melt freeze crust will form on all aspects and elevations. The depth of the mid-January surface hoar is highly variable across the region and it may have been destroyed by the warm snow at lower elevations. Where it does exist it can be found between 20 and 50 cm below the surface. The mid-December surface hoar layer lies below a strong mid-pack down 60 to 120cm and appears to be gaining strength. The mid-November weak layer of crusts and facets can still be found near the bottom of the snowpack. It has been unreactive lately.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.