Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Dec 8th, 2021–Dec 9th, 2021

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.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural and human triggered avalanches likely.
Below Treeline
Natural avalanches unlikely, human triggered possible.

Regions

South Coast Inland.

 Areas with thicker pillows of wind-drifted snow are the primary concern as they're covering a hard, smooth, slippery crust. Be cautions near ridges, ribs, and cross-loaded gulleys.

Confidence

Moderate - Uncertainty is due to limitations in the field data.

Weather Forecast

Thursday and Friday should be quiet with the next storm arriving Friday overnight.

OVERNIGHT: Trace of snow, temperatures around -5 to -10 C, moderate to strong west wind.

THURSDAY: Trace to a few centimetres of snow. Continued cold with temps around -10 C. Light to moderate westerly wind.

FRIDAY: Flurries up to 5 cm. Moderate southwest wind. Treeline high temperatures around -10 C. The next storm arriving late in the day ....

SATURDAY: Sunrise should show 10 - 20 cm of new snow which should double in depth by sunset. Moderate to strong southwest winds. Warmer temperatures with freezing level rising to around 1500m.

Avalanche Summary

We have no new avalanche observations from this region; quite possibly due to travel restrictions. If you are out in places like the Hurley and see avalanches please drop a MIN.

Snowpack Summary

Upper snowpack: 10-20 cm of recent snow is covering wind affected surfaces including the Dec01 crust.

The south, having endured warmer temperatures and more rainfall, is largely below threshold for avalanches at most elevations. Previous snow has seen extensive wind effect, exposing the rain crust clean in some areas, while piling up to 40 cm over it in others.

In the north, the new snow may be sitting over a layer of surface hoar crystals, older wind affected snow in the alpine, a thick crust below 1800 m or a combination of these.

A couple of buried weak layers produced large avalanches during a previous storm. If these layers remain active they'll be confined to alpine elevations.These include a layer of surface hoar down an estimated 90-120 cm and deeper crust/facet combo layer.

Average snowpack depths in the alpine are 150-200 cm. Below treeline, depths of 30-50 cm around 500 m.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Make observations and assess conditions continually as you travel.
  • Closely monitor how the new snow is bonding to the old surface.
  • Keep in mind the crust offers an excellent bed surface for avalanches.

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.