Avalanche Forecast
Issued: Dec 10th, 2023 4:00PM
The alpine rating is Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeWind slabs at treeline and above are the main concern.
Use extra caution below ridgecrests, roll-overs and in gully features. Watch for signs of instability like shooting cracks.
Summary
Confidence
Moderate
Avalanche Summary
On Saturday, avalanche control produced several small to large avalanches (up to size 2). The general trend was storm slab avalanches to the west, and wind slab avalanches to the east.
A widespread natural avalanche cycle was observed during the storm towards the end of the week, producing loose wet and storm slab avalanches up to size 2.5.
Snowpack Summary
Recent moderate to strong southwest winds have likely redistributed surface snow into deeper, more reactive pockets in leeward terrain features. In some areas, you may also find a thin, frozen crust on the surface.
40-60 cm of recent snow seems to be bonding well to the wet or frozen surface left behind by recent, heavy rain. A hard melt-freeze crust is forming at this interface, observed up to 5 cm thick in some places.
Beneath the upper crust, the remainder of the rain-moistened snowpack is slowly refreezing as freezing level remains below valley bottom.
Snowpack depths vary across the forecast area. 50 to 120 cm at treeline, tapering rapidly below treeline.
Weather Summary
Sunday Night
Cloudy. 0-2 cm of snow expected. Moderate southwest ridgetop wind tapering off to light and variable by the morning. Treeline temperature around -5°C.
Monday
Cloudy, possible clearing in the late afternoon. No new snow expected. Light southwest ridgetop wind. Treeline high around -5 °C.
Tuesday
Mostly sunny. No new snow expected. Light southwest ridgetop wind. Treeline temperature around -4 °C.
Wednesday
Partly cloudy. No new snow expected. Moderate southwest ridgetop wind. Freezing level rising to 1500 m, with a possible above freezing layer at high elevations.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
- Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.
Problems
Wind Slabs
More likely on the Rockies side of the forecast area. Several wind stations aren't reporting, so the extent of wind transport is uncertain. Watch out for reactive windslabs in leeward terrain features such as ridgecrests and roll-overs.
Aspects: North, North East, East, South East, South, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 11th, 2023 4:00PM