Avalanche Forecast
Issued: Dec 29th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
jleblanc,
Avalanche Canada
With these frigid temperatures, be aware that even a small incident may have serious consequences. The best and safest riding will be on slopes that have soft snow without any slab properties.
Summary
Confidence
Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.
Weather Forecast
A system, approaching from the north, is aiming at the B.C. coast, with light snow but strong steady winds into the NW ranges. Thursday, an arctic ridge of high pressure will re-establish itself, leading to another clear and cold day heading into Friday. The next round of snow is expected Saturday.
WEDNESDAY NIGHT: Light snow 3-5 cm / Strong west winds at treeline / Low of -15
THURSDAY: Clearing throughout the day / Moderate north winds at treeline / Possible temperature inversion with -25 at the valley bottom and -15 at 1500 m.
FRIDAY: Cloudy with snow expected late afternoon / Light northwest winds at treeline / Possible temperature inversion with -30 at the valley bottom and -15 at 1500 m.
SATURDAY: Snow 10-15 cm / Strong to extreme southwest winds at treeline/ High of -10
Avalanche Summary
A small (size 1) wind slab avalanche was easily triggered by a snowmobile Wednesday on a convex roll at treeline. Intense snow transport and drifting were observed in the alpine.
Explosives triggered numerous large wind slabs (size 2) with good propagation on alpine lee North-facing slopes in the southern part of the region.
If you are out in the mountains please consider filling out a Mountain Information Network report.
Snowpack Summary
New snow and wind forecasted for Wednesday night will have formed fresh and reactive wind slabs at treeline and alpine, predominantly found on east aspects. In some areas, wind slabs are sitting on a weak surface of faceted snow due to last week's cold temperatures.
Significant faceting was also observed over the thick early December crust, which can still be found down 70 cm around 1800 m.Â
Snowpack depth at treeline typically ranges from 120-220 cm, with higher values in the western part of the region and tapering to the east.Â
Terrain and Travel
- Sheltered slopes at lower elevations will offer the best riding.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
Problems
Wind Slabs
The recent and current storms have left plenty of fresh snow for wind transport. Reactive wind slabs have developed all day Wednesday on east alpine slopes and open areas at treeline. Older and harder slabs are also present on west slopes due to outflow.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 30th, 2021 4:00PM
