Regions
Northwest Coastal.
Conditions are improving, but windslabs remain a concern at treeline and above.
Confidence
Good - Due to the number and quality of field observations on Monday
Weather Forecast
Cloudy with cool temperatures and small amounts of new snow in the forecast for the next few days, then the arctic ridge of high pressure will rebuild and again dominate the Province bringing even cooler temperatures and very little precipitation.
Avalanche Summary
2, size 2.5 naturally occuring wind slab avalanches were reported yesterday on west facing slopes around 1500 metres. Reports of natural avalanche activity re slowing down, but the potential for rider triggering remains a concern.
Snowpack Summary
Storm snow amounts vary widely across the region. Southern areas received close to 1m of new snow, but northern areas reported receiving half of that. Strong winds have redistributed the recent storm snow, and rain in some areas has produced a surface crust layer that will be of concern with future snow loading. A buried surface hoar layer in the mid-snowpack is still on the radar in some northern sections , and the mid December crust can still be found in the middle of the snowpack. This layer has been reported to be sandwiched between facets and surface hoar in some places. The November crust near the bottom of the snowpack is generally well bonded but may still be reactive in areas with shallow 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.