Avalanche Forecast
Issued: Dec 9th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
lbaker,
Avalanche Canada
Though it has stopped snowing strong winds switching to the east are redistributing storm snow into a more cohesive slab keeping avalanche hazard elevated in the alpine.
Watch for signs of instability such as whumpfing, cracking, and recent avalanches.
Summary
Confidence
Moderate
Avalanche Summary
Numerous natural storm slabs and loose dry avalanches, to size 2, were reported Thursday at all elevations. Avalanches are suspected to have released on the recently buried surface hoar layer. As visibility improves over the next few days expect to see further evidence of the storm cycle.
If you head out in the backcountry please support your community by submitting a MIN report!
Snowpack Summary
20 - 30 cm of storm snow has buried a layer of surface hoar, size 5-10 mm, and facets. Surface hoar overlies wind-hammered surfaces including scoured easterly slopes and hard slabs on west and south slopes.
A layer that formed in mid-November can be found down 70 to 100 cm deep at treeline and above. This layer consists of a crust below 1200 m and a layer of surface hoar above this elevation. This layer has not shown recent signs of instability.
The depth of the snowpack at treeline varies widely from 100 to 200 cm and tapers rapidly below treeline. Many early-season hazards such as rocks, stumps, and open creeks exist below treeline.
Weather Summary
Friday Night
Cloudy with scattered flurries, 2 - 5 cm accumulation. Ridge winds southwesterly 30 - 40 km/h. Temperatures are -8 at 1500 m. Freezing levels 300m.
Saturday
Mix of sun and cloud with isolated flurries, trace accumulation. Moderate outflow winds through mainland inlets. Ridgetop winds will be easterly 40 - 60 km/h. Temperatures are -10 at 1500 m. Freezing levels valley bottom.
Sunday
Mostly sunny with cloudy periods. Strong outflow winds in valleys. Moderate outflow winds through mainland inlets. Ridge winds northerly 20 - 30 km/h. Temperatures are -11 at 1500 m. Freezing levels valley bottom.
Monday
Mix of sun and cloud. Strong outflow winds in valleys. Ridge winds northerly 20 to 30 km/h. Possible inversion with alpine temperatures reaching a high of -2 and low of -8. Freezing levels 500m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Fresh wind slabs will likely form throughout the day, diligently watch for changing conditions.
- Start with conservative lines and watch for clues of instability.
- Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.
Problems
Storm Slabs
20 - 30 cm of storm snow now sits atop a preserved layer of surface hoar/facets. As wind redistributes snow into deeper pockets and the slab becomes more cohesive we should expect it to become more reactive.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 10th, 2022 4:00PM
