Avalanche Forecast
Issued: Dec 7th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
ahanna,
VIAC
New snow and wind are forming fresh slabs. We have uncertainty around the reactivity of two near-surface crusts. Take a conservative approach and investigate the bond at these interfaces before stepping into more committing terrain.
Summary
Confidence
Moderate - Uncertainty is due to limitations in the field data.
Weather Forecast
Tuesday night: New snow 10-20 cm. Strong westerly wind. Freezing leveldropping 1500- 800 m.
Wednesday: A mix of sun and cloud. Strong northwest wind. Treeline high temperatures around -5. Freezing level 700 m.
Thursday: A mix of sun and cloud. Moderate northwest wind. Treeline high temperatures around -4. Freezing level 700 m.
Friday: Snow starting 5-10 cm. Strong southwest wind. Treeline high temperatures around -1. Freezing level 1000 m.
Avalanche Summary
No recent reports.
Snowpack Summary
10-20 cm of overnight snow fell amid strong wind, likely loading deeper deposits into lee features at upper elevations. The new snow may sit over a thin crust that formed when 20-40 cm of recent snow warmed up on Tuesday. This recent snow may be sitting over a weak layer of surface hoar crystals or facets over a thick crust.
Recent indications of the region's snowpack suggest alpine depths around 150- 200 cm, depth tapering dramatically with elevation to about 40-80 cm at treeline. Below treeline is below threshold for avalanches.
Terrain and Travel
- Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
- Start with conservative lines and watch for clues of instability.
- Closely monitor how the new snow is bonding to the crust.
- Keep in mind the crust offers an excellent bed surface for avalanches.
Problems
Storm Slabs
New snow and wind are forming fresh slabs over a thin crust. Recent snow under this crust is well-settled and dense and may remain reactive where it sits over a weak layer of surface hoar on a thicker crust. You can dig down to investigate the bond at these interfaces.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 8th, 2021 4:00PM
