Avalanche Forecast
Issued: Dec 5th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
rgoddard,
Avalanche Canada
Snow and rain continue to place stressors on the snowpack.
Natural and human-triggered avalanches should be expected.
Summary
Confidence
Avalanche Summary
Local operators produced numerous storm slab avalanches with the use of explosives on Monday.
Several size one to two natural and skier-triggered avalanches were reported in our region this past weekend. Many of these were remotely triggered and ran on the buried surface hoar layer. These avalanches occurred at treeline elevation and on all aspects.
Snowpack Summary
By Wednesday morning up to 40 mm of precipitation falling as rain and/or snow will have been added to the snowpack. This heavy load will be weighing on up to 40 cm of snow that fell this weekend. The layer of greatest concern, large buried surface hoar, can be found just below this recent snow.
On steep south-facing slopes, this surface hoar sits on a thin sun crust. At higher elevations, the weekend's snow will have formed wind slabs on north and east-facing slopes.
The mid-pack is generally well-settled. Lower in the snowpack a crust with sugary facets beneath it can be found 20 cm off the ground.
Weather Summary
Tuesday Night
Cloudy, 5 to 10 cm accumulation of rain and snow with up to 20 in the far east, alpine winds southwest 25 to 35 km/h, freezing level as high as 2000 m.
Wednesday
Mostly cloudy, 15 to 20 cm accumulation above 1500 m and rain in the valley, alpine winds westerly 25 to 35 km/h, freezing level at starting at 2000 m and decreasing throughout the day.
Thursday
Cloudy with possible sunny breaks, 2 cm accumulation, alpine winds west 10 to 20 km/h, treeline temperatures around -6 °C.
Friday
Mix of sun and cloud, up to 8 cm accumulation, alpine winds west 5 to 15 km/h, treeline temperatures around -8 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Remote triggering is a concern, watch out for adjacent and overhead slopes.
- 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.
- Minimize exposure during periods of heavy loading from rain.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Problems
Storm Slabs
Snow and rain continue to accumulate and create a heavy load on a weak surface hoar layer in many areas. Expect to find reactive storm slabs in areas where it is not raining.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
A mix of snow and rain will make wet loose avalanches likely at lower elevations.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Dec 6th, 2023 4:00PM
