Avalanche Forecast
Issued: Dec 4th, 2013 4:01PM
The alpine rating is Persistent Slabs and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems include10-20 cm was received in the forecast area earlier in the week, with the greatest amounts in the Eastern part of the region. Cold temperatures will remain and expect a gradual weakening of the snowpack support.
Summary
Weather Forecast
The alpine temperatures will dip to -30 by Friday, but become slightly warmer by the weekend to -20C for a high. Winds will remain light from the North. The Arctic high pressure will be in the region for the next several days.
Snowpack Summary
10-15 cm fell with moderate- strong North winds as the Arctic air moved in 2 days ago. Some reverse loading of slopes may have created some new windslabs in the alpine. There is 65-85 cm at our treeline study plots and some mid-pack support for skiing. Field tests still show failures on the Oct 27 crust where it exists or on the basal facets.
Avalanche Summary
In the last 24 hours, a size 2 avalanche occurred on a NW aspect of Copper Mountain, just west of Banff, at about 2350 m. It started as a point release which then triggered a 80 m wide slab that failed near ground, down 100-150 cm.
Confidence
Problems
Persistent Slabs
The October melt freeze crust and basal depth hoar are a a concern and avalanches may step down to basal layers. This is primarily a concern on steeper features especially if they are windloaded.
- Resist venturing out into complex terrain, even if you observe no obvious signs of unstable snow.
- Conditions are greatly improved, but be mindful that deep instabilities are still present.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Reverse loading has created new slabs on southerly aspects. Although less reactive with the colder temperatures, watch out for lingering wind slabs on N-NE aspects.
- Be careful with wind loaded pockets while approaching and climbing ice routes.
- The new snow will require several days to settle and stabilize.
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 5th, 2013 4:00PM