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

Nov 26th, 2019–Nov 27th, 2019

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

Regions

Kootenay Boundary.

Cold, windy weather is in the forecast for Wednesday. With a recent change in wind direction you may find wind slabs on all aspects.

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Tuesday Night: Cloudy with isolated flurries bringing trace amounts of snow to eastern parts of the region, wind increasing to 50 km/h from the northeast, alpine temperatures dropping to -12 C.

Wednesday: Mostly cloudy with isolated flurries bringing trace amounts of snow to eastern parts of the region, 50-70 km/h wind from the northeast, alpine temperatures dropping to -17 C.

Thursday: Sky clearing through the day, wind easing to 20-30 km/h from the northeast, alpine temperatures around -15 C.

Friday: Clear skies, light wind from the northeast, alpine temperatures rising to -10 C.

Avalanche Summary

The most likely place for avalanches to be triggered right now is on slopes where the wind has blown surface snow into wind slabs. A MIN report from the weekend shows the type of terrain where triggering thin wind slabs is a concern. This group of skiers reported a 20 cm thick slab that was triggered on north-facing slope at 2100 m. Observations are limited this time of year, so there is a fair bit of uncertainty about the extent of current avalanche activity.

Snowpack Summary

A recent change in wind direction from southwest to northeast is expected redistribute surface snow, resulting in wind slabs on all aspects. Beneath this, the snow pack consists of various crusts and a potential feathery, weak surface hoar layer 50 cm below the surface (see video here). With few field observations, uncertainty remains on the distribution and reactivity of these layers. It's still early season and the snow pack remains fairly thin. At the deepest, up to 100 cm can be found on north aspects in the alpine.

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.