Avalanche Forecast
Issued: Dec 17th, 2023 4:00PM
The alpine rating is Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeContinue to be wary of a buried layer of surface hoar. Use good travel habits to avoid getting caught off guard.
Read our Forecasters' Blog for details on a persistent slab problem in the region
Summary
Confidence
Moderate
Avalanche Summary
On Saturday, explosives control produced a few, size 1, wind slab avalanches on lee terrain features in the alpine.
If you go out in the backcountry, please consider sharing your observations on the Mountain Information Network (MIN).
Snowpack Summary
A dusting of snow has buried a layer of surface hoar and sun crust. A prominent rain crust is found 30 to 60 cm deep. While the dry snow above the crust is bonding well, in some areas below the crust is a layer of large weak surface hoar crystals. It may be possible to trigger this surface hoar layer in areas where the crust is thinner and less supportive, with higher-elevation terrain being the most suspect. Typical snowpack depths at treeline are 70 to 110 cm, and taper rapidly below treeline.
Weather Summary
Sunday Night
Mainly clear with no precipitation, alpine wind west 30 to 50 km/h, treeline temperature 0 °C with a possible temperature inversion.
Monday
Mix of sun and cloud with no precipitation, alpine wind southwest 30 to 40 km/h, treeline temperature 0 °C with a possible temperature inversion.
Tuesday
Cloudy with scattered flurries, 2 to 7 cm accumulation, alpine wind southwest 30 to 50 km/h, treeline temperature -4°C.
Wednesday
Cloudy with isolated flurries, 2 to 5 cm accumulation, alpine wind west 20 to 30 km/h, treeline temperature -3°C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Carefully evaluate bigger terrain features on an individual basis before committing to them.
- Surface hoar distribution is highly variable. Avoid generalizing your observations.
- Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.
Problems
Persistent Slabs
A preserved layer of surface hoar is found down 30 to 60 cm. At higher elevations where the weak layer is not being capped by a rain crust, it may be possible to human-trigger.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 18th, 2023 4:00PM