Regions
Kootenay Boundary.
Avalanche hazard will continue to decrease as the temperature cools, however pay attention to conditions that change between aspects.
Confidence
Moderate - Freezing levels are uncertain
Weather Forecast
FRIDAY: wet snow, up to 10cm overnight and through the day, light southerly winds, freezing level of 1800m. SATURDAY: another 5-10cm of snow overnight, becoming scattered flurries through the day, light westerly winds, freezing level of 1500m. SUNDAY: Light snow through the day, light southwest winds, freezing level of 1700m
Avalanche Summary
Loose wet avalanche activity up to size 2 has been associated with the warm temperatures and strong solar radiation.
Snowpack Summary
Wet or moist snow can be found on solar aspects at all elevations. A thin melt freeze crust may have form surface overnight. Dry snow can still be found on high north facing slope where increasingly hard to trigger wind slabs can be found at ridgeline. A layer of surface hoar has been observed around Rosland and in the Bonnington Range, buried down 40cm, in open areas at and just below treeline. In most other parts of the region a rain crust can be found at this same depth that extends up as high as 2100m.Below this, a thick slab rests on a layer of surface hoar that was buried earlier in January and is now down 80-130 cm. This layer remains a concern in at and bellow treeline, producing sudden planar fractures in snowpack tests under moderate to heavy loads. I'm going to keep it on my radar until the snowpack cools off again. A rain crust from early December sits near the base of the snowpack.
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.