Regions
Kootenay Boundary.
The snow is heavily wind-affected. Stick to sheltered trees to find the best and safest riding.
Confidence
Moderate - Wind speed and direction is uncertain
Weather Forecast
TUESDAY: Mix of sun and cloud, light north wind, alpine high temperatures around -17 C.WEDNESDAY: Mostly sunny, light northwest wind, alpine high temperatures around -15 C. THURSDAY: Mostly sunny, light wind, alpine high temperatures around -12 C.
Avalanche Summary
Widespread storm slab activity was reported on all aspects and elevations on Sunday, including natural avalanches up to size 2 and smaller skier-triggered avalanches (size 1). Similar activity was also reported the previous two days. Looking ahead, natural storm slab activity will wind down but human-triggering remains likely.No avalanches have been reported on persistent weak layers for over a week.
Snowpack Summary
Gusty wind from various directions (primarily northeast) has scoured some exposed slopes and formed fresh wind slabs on others. Sheltered terrain has 30-50 cm of low density snow from recent storms. A crust layer can be found beneath the storm snow on sun-exposed slopes and below 1800 m, but these interfaces have not been involved in recent avalanches.Weak layers that formed in January and December are gradually gaining strength. The layers include several surface hoar and facet layers buried 1-2 m below the surface. No avalanches have been reported on these layers for the past week and snowpack tests are showing improved bonding. Despite these signs, avalanche professionals are still treating these layers with respect and being cautious around shallow start zones and big avalanche paths.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.