Avalanche Forecast
Issued: Dec 13th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
LP,
Avalanche Canada
A few wind triggered avalanches occurred on Wednesday. The basal snowpack layer remains weak and untrustworthy. Conservative route choices are still advised.
Summary
Confidence
Moderate
Avalanche Summary
A few wind triggered avalanches up to size 2 were observed Wednesday above Pilsner Pillar ice climb and in extreme terrain in Chickadee Valley. There have been more reports with the good visibility of avalanches up to size 2.5 that occurred after last weeks storm. Most originated in the alpine but some originated in treeline locations. On Saturday a size 2 skier triggered avalanche failed as a deep persistent slab at treeline and ran 600m scrubbing to ground.
Snowpack Summary
Wind affect in the alpine from Wednesdays strong SW winds. At treeline, last week's storm snow has settled to 20-40cm over the Dec 2 weak layer which consists of the basal facets and surface hoar. A rain crust (1 to 7cm thick) exists within the storm snow up to 2300m on all aspects. The thickness of the rain crust tapers with increasing elevation and is more prevalent in the southern part of the region. Click here for snow profile done on Tuesday in the Dolomite peak area.
Weather Summary
Winds decrease to moderate Wednesday night as flurries move into the region Thursday bringing 5-10 cm. Snow ends Thursday night and winds again pick up to strong on Friday. At treeline, the overnight lows will be around -10C with daytime highs around -5C for the next couple of days.
For more information, click Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Problems
Wind Slabs
Strong SW winds on Wednesday created some new reactive windslabs in alpine and exposed treeline terrain. Winds diminish Thursday and the incoming flurries may hide existing windslabs.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Surface windslab avalanches have the potential to step down to the basal facets resulting in larger full depth avalanches. Given the weak snowpack structure, avalanches in motion have the potential to run further than expected into below treeline terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 14th, 2023 4:00PM
