Avalanche Forecast
Issued: Dec 22nd, 2019 5:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
dsaly,
Avalanche Canada
Snow is gradually accumulating and consolidating above a recently buried layer of surface hoar. Best to make conservative terrain choices at this time.
Summary
Confidence
Low - Uncertainty is due to unpredictable avalanche behavior. Uncertainty is due to the limited number of field observations.
Weather Forecast
Sunday Night: Mainly cloudy. Alpine temperature -5 C. Light to moderate southwest wind. Freezing level 300 m.
Monday: Flurries, 5-15 cm and up to 20 cm near Kitimat. Alpine temperature -5 C. Moderate south wind. Freezing level 600 m.
Tuesday: Scattered flurries, 5-10 cm. Alpine temperature -5 C. Moderate southwest wind. Freezing level 500 m.
Wednesday: Mix of sun and cloud. Alpine temperature -6 C. Light to moderate south wind. Freezing level 400 m.
Avalanche Summary
Natural storm slab to size 2 avalanches were reported in the Shames area on Thursday. Further north in the region, explosives triggered storm slab avalanches to size 2.
A MIN report here from Saturday identifies and discusses reactive surface hoar buried 70 cm under the recent storm snow.
Snowpack Summary
50-80 cm of snow has accumulated over a weak layer of surface hoar, old faceted surfaces, and/or a crust on south/southwest aspects in the alpine. Reports from the Shames area suggest the surface hoar layer is prevalent on all aspects at treeline elevations down to 800 m, and more likely on leeward and sheltered alpine areas.
The lower snowpack is generally considered strong, as there has been very little to report in terms of recent avalanche activity or snowpack test results on deeper layers. Snowpack depths at treeline range from 100-200 cm and taper quickly at lower elevations.
Terrain and Travel
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Be careful as you transition into wind affected terrain.
- Uncertainty is best managed through conservative terrain choices at this time.
Problems
Storm Slabs
50-80 cm snow has accumulated over a weak layer of surface hoar. It is uncertain when this layer may become reactive as the snow above gradually accumulates and consolidates. Certainly it is right at the tipping point, so making conservative terrain choices is the best way to manage this problem.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 23rd, 2019 5:00PM
