Avalanche Forecast

Issued: Dec 8th, 2023 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Storm Slabs.

Avalanche Canada wlewis, Avalanche Canada

Email

Natural activity has tapered off, but human triggering is still possible.

Choose conservative terrain, minimize exposure to large avalanche paths and overhead hazard.

Summary

Confidence

Moderate

Avalanche Summary

A widespread natural cycle occurred on Tuesday and Wednesday, with large storm slabs, and wet avalanches in areas that received mostly rain. Avalanches ran on the buried surface hoar layer or within the storm snow.

While storm snow avalanches are tapering off, the highest danger for continued reactivity exists in areas where the rain crust thins, or does not exist. Remotely triggered avalanches occurred in these conditions in nearby regions, on the buried surface hoar.

Snowpack Summary

Strong winds will redistribute 10-20 cm of recent snow into deeper deposits on north and east facing slopes. This snow covers a widespread crust from the rain. In the south, this crust is up to 25 cm thick and extends to ridgetop. The crust thins to around 5 cm as you move north from Revelstoke, and is observed up to 2300 m.

The greatest concern is a large and weak layer of surface hoar, found 45-80 cm deep. This surface hoar sits on a thin sun crust on steep south-facing slopes. In some areas, the surface hoar has been saturated by the rain and is decomposing.

The mid-pack is generally well-settled. Lower in the snowpack a crust with weak facets beneath it can be found 20 cm off the ground.

Weather Summary

Friday Night

Partly cloudy, with westerly winds 20 km/h. No snowfall expected. Treeline temperatures around -8 °C.

Saturday

A mix of sun and cloud with light snowfall in the afternoon delivering up to 5 cm. Treeline temperatures around -8 °C. Southwest winds increase to 40-60 km/h.

Snow continues overnight with 10 cm possible.

Sunday

Cloudy with another 10 cm of snow possible. Winds ease to 40 km/h from the west. Treeline temperatures around -7 °C.

Monday

Cloudy with no snow expected. Light and variable winds. Treeline temperatures reach -4 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
  • Use careful route-finding and stick to moderate slope angles with low consequences.

Problems

Storm Slabs

An icon showing Storm Slabs

Expect greater reactivity where slabs sit on a layer of buried surface hoar (think convex rolls and sheltered treeline areas). Avoid exposure to large slopes that did not avalanche in the storm.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Dec 9th, 2023 4:00PM