Avalanche Forecast
Issued: Dec 13th, 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.
swerner,
Avalanche Canada
Make conservative terrain choices. Persistent slabs may be reactive to human triggering, especially at treeline and above.
Summary
Confidence
Moderate
Avalanche Summary
On Tuesday, sloughing was seen from steep terrain features but no significant avalanches were reported.
Natural avalanche activity has tapered, but human-triggered avalanches remain possible at higher elevations, particularly where slabs sit over the weak surface hoar.
Snowpack Summary
New snow expected on Thursday will bury a variety of snow surfaces including wind-affected snow, sun crusts on steeper south aspects and surface hoar. Down 25-50 cm a rain crust has been observed and exists up to 2200 m throughout this region. The thickness of this crust tapers with elevation gain.
A concerning layer of surface hoar is now buried 60 to 90 cm deep at upper elevations and may be more reactive to human triggering above 2200 m.
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
Wednesday Night
Mainly cloudy with light snowfall amounts. Ridgetop wind 15 to 45 km/h from the south and temperatures near -5 C. Freezing levels 800 m.
Thursday
Cloudy with snowfall, 5 to 15 cm of accumulation. Ridgetop wind 15-35 km/h from the south. Alpine temperature around -4 C. Freezing levels 1500 m.
Friday
A mix of sun and cloud. Alpine winds are light from the south with temperatures near -4 C. Freezing levels 900 m.
Saturday
Mix of sun and cloud. Ridgetop wind 15 gusting to 65 km/h and temperatures near -2. Freezing levels 1400 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Stay off recently wind loaded slopes until they have had a chance to stabilize.
- Use conservative route selection and resist venturing out into complex terrain.
- Be aware of the potential for larger than expected storm slabs due to the presence of buried surface hoar.
Problems
Wind Slabs
Strong southerly winds and fresh snow may build fresh wind slabs. They may be thicker and more reactive in north and east-facing terrain features.
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 at treeline and alpine elevations. It may be most triggerable where the recent rain crust thins, or disappears.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 14th, 2023 4:00PM
