Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Regions
Cariboos.
A stable weather pattern to start the new year and possible temperature inversion coming mid-week. Consider the potential to trigger persistent slabs as the recent storm snow starts to finally settle and consolidate more rapidly.
Confidence
Moderate - Freezing levels are uncertain on Wednesday
Weather Forecast
MONDAY: Mix of sun and cloud / Light to moderate northwest wind / Alpine temperature -12TUESDAY: Mix of sun and cloud / Light to moderate west wind / Alpine temperature -5, possible temperature inversion WEDNESDAY: Cloudy with sunny breaks / Light southwest wind / Alpine temperature -1, temperature inversion
15-30cm of low density new snow has buried a recently formed layer of weak feathery surface hoar and/or sugary facets. A layer buried mid-December that consists of surface hoar, sun crust and/or sugary facets is now down approximately 30-50cm. The bond at this old snow interface is of critical importance in areas where the overlying snow has consolidated into a slab. The most concerning areas are those that saw pronounced surface hoar development before the storm, such as sheltered areas at and below treeline, sheltered northerly aspects in the alpine, or anywhere the surface hoar formed on top of a sun crust. Recent snowpack tests show wide ranging reactivity on this weak layer. A crust which was formed by rain in late November is another major feature in the snowpack and is down approximately 70-100cm at tree line elevations. This interface has shown some signs of reactivity in the adjacent North Columbia region limited to steep, variably loaded alpine features.
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.