Avalanche Forecast
Issued: Dec 11th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
rgoddard,
Avalanche Canada
Watch for signs of instability like natural avalanches, whumpfing, and shooting cracks as you travel through the terrain.
Wind slabs at treeline may have formed over touchy surfaces like crusts and surface hoar making them larger and more sensitive to triggering.
Summary
Confidence
Avalanche Summary
No new avalanches have been observed or reported in this region. However, note that we have had very few field observations and much of our forecast has been extrapolated from our surrounding neighbours. Please consider filling out a Mountain Information Network report if you are heading to the backcountry.
Snowpack Summary
Saturday night brought another dusting to some parts of our region, ranging from 8 cm in the southwest to zero in the northeast. This adds to Friday night's totals of between 2 and 10 cm. These amounts came with minimal wind. Earlier in the week, southerly winds redistribute snow into wind slabs on west, north, and east aspects. A slight warming may help consolidate the fresh snow and produce a slab depending on the nature of the surface it is sitting on. There were reports of finding buried a layer of surface hoar 20 cm down in sheltered terrain and a sun crust on south-facing slopes.
A concerning layer of surface hoar from mid-November is buried down up to 40 to 60 cm. This layer could become more reactive as slab properties above it increase with new snow and wind.
Weather Summary
Sunday Night
Mostly clear, no accumulation, winds northeast 15 km/h, temperature -6 C at 1500 m.
Monday
A mix of sun and cloud, no accumulation, winds northeast 15 km/h, temperature -6 C at 1500 m.
Tuesday
Mostly sunny, no accumulation, winds northwest 10 to 15 km/h, temperature -5 C at 1500 m.
Wednesday
Cloudy with sunny periods, 2 cm accumulation, winds north 10 km/h, temperature -5 to -8 C at 1500 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
Problems
Persistent Slabs
A surface hoar layer from mid-November is buried down 40 to 60 cm in the region. As snow continues to fall adding load to the snowpack it is likely that this layer is approaching a tipping point where it will become more sensitive to rider triggering. Use extra caution at the treeline where this layer is more prominent and look for signs of instability and a stiff feeling of snow.
There has been very little reporting on layer but it has been producing avalanches for our nearest neighbours. Use caution and assess the snow as you go.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
A light dusting of snow covers wind slabs created earlier in the week.
Wind slab avalanches could step down to deeper layers resulting in large destructive avalanches.
Aspects: North, North East, East, South East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 12th, 2022 4:00PM
