Natural avalanches possible, human triggered probable.
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
Sea To Sky.
Expect to find extensive wind effect, resulting from recent extreme winds. Travel cautiously and observe for the bond of the snow with underlying layers before committing to avalanche terrain.
Confidence
High -
Weather Forecast
SATURDAY NIGHT: Cloudy, light to moderate west winds, freezing level 1000 m.SUNDAY: Clearing skies, light northwest winds, alpine temperature -7 C, freezing level 900 m.MONDAY: Clear with a few clouds, light northwest winds, alpine temperature -8 C, freezing level 600 m.TUESDAY: Cloudy with light snowfall, light to moderate southwest winds, alpine temperature -6 C, freezing level 700 m.
Avalanche Summary
Many small to large (size 1 to 2) slab avalanches with the storm snow were triggered naturally, by skiers, and with explosives on Friday and Saturday. See here for an example.
Snowpack Summary
Around 20 to 30 cm of recent snow fell in the region, with associated extreme south winds. This snow fell onto a sun crust on south aspects, a temperature crust below 1700 m on all aspects, and feathery surface hoar in sheltered and shaded areas at all elevation bands. The new snow may not bond well to these layers.Below this, the snowpack is generally well-settled.
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.