Avalanche Forecast
Issued: Dec 10th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
wlewis,
Avalanche Canada
Continue to be conservative with terrain choice.
Storm snow and buried weak layers remain primed for human triggering at higher elevations.
Summary
Confidence
Avalanche Summary
Natural and human triggered avalanche activity has tapered off. Recent reports in nearby regions include remotely triggered avalanches on the buried surface hoar layer. Whumpfing has been observed throughout this region - this is a sure sign of instability on a buried weak layer!
Human triggered avalanches are still possible at higher elevations, where slabs sit over the weak surface hoar.
Snowpack Summary
The recent 30-50 cm of storm snow has likely been redistributed into deeper deposits on north and east facing slopes at higher elevations. This sits over a rain crust that has been observed up to 1800-2200 m throughout this region.
A concerning layer of surface hoar is now buried 60-90 cm deep. A widespread natural cycle may have destroyed this layer in steep features but it likely still lingers unaffected features.
The lower snowpack is a mix of rounded and faceted grains. A hard crust may be found near the ground.
Treeline snowpack depths are variable and generally range between 60 and 100 cm. Snowpack tapers rapidly as you move lower in elevation.
Weather Summary
Sunday Night
Mostly cloudy, up to 5 cm of snow possible. Southwest winds 30-40 km/h. Freezing levels return to valley bottom.
Monday
Mostly cloudy, no snowfall expected. Treeline temperatures around -7 °C. Light and variable wind.
Tuesday
Clearing skies with no snowfall expected. Southerly winds, 30-50 km/h. Treeline temperatures around -9 °C.
Tuesday
Clearing skies with no snowfall expected. Southerly winds, 60-80 km/h. Treeline temperatures around -7 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Make conservative terrain choices and avoid overhead hazard.
- Be aware of the potential for larger than expected storm slabs due to the presence of buried surface hoar.
- Stay off recently wind loaded slopes until they have had a chance to stabilize.
Problems
Wind Slabs
Winds have built deeper and more reactive slabs in north and east facing terrain features. Slabs sit over a rain crust below ~2100 m. At higher elevations, slabs sit over recent storm snow - and may step down to the buried surface hoar layer.
Aspects: North, North East, East, South East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Buried surface hoar is most likely to be found on treeline and sheltered alpine slopes, and most triggerable where the recent rain crust thins, or disappears.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 11th, 2023 4:00PM
