Riding conditions will probably be good tomorrow but don't forget about the persistent weaknesses that are lurking deeper in the snow pack.
Confidence
Poor - Due to the number and quality of field observations
Weather Forecast
A frontal system will bring another 10 to15cm of new snowfall to the region overnight on Monday with scattered flurries expected for Tuesday in its wake. A ridge of high pressure building over the province Wednesday will bring dry conditions. Winds will be predominantly light from the west to southwest. Freezing levels will remain at valley bottom.
Avalanche Summary
There was a widespread avalanche cycle earlier in the week that produced numerous large to very large avalanches. Natural activity has now eased, but the present of persistent layers in snow pack suggest that it may be possible for humans to trigger an avalanche.
Snowpack Summary
Up to 35cm of new snow fell over the weekend. This new snow sits on a variety of old surfaces. A crust can found below about 1900m in the north of the region and 2200m in the south. At higher elevations the new snow covers old wind slabs formed by moderate southwest winds. Several persistent week layers can be found deeper in the snowpack but are probably protected by the overlying crust at lower elevations. The mid-January surface hoar is buried between 40 and 80cm down and remains a concern at treeline and above. The mid-December surface hoar layer is now 80 to 140cm below the surface and appears to be slowly gaining strength. The base of the snowpack is faceted.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
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.