Avalanche Forecast
Issued: Dec 11th, 2017 4:55PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs.
brian webster,
Parks Canada
A strong temperature inversion results in above freezing temperatures in the alpine. Ice climbers be cautious, now is a good time to avoid being under south facing slopes in the afternoon.
Summary
Weather Forecast
The high pressure ridge will dominate the region until at least Thursday. Temperatures will remain inverted with above freezing temperatures in the alpine and cooler temperatures at the valley bottoms. A weak upper low crossing the region on Tuesday will cause some high level cloud cover and some stronger winds but no precipitation is expected.
Snowpack Summary
Small surface hoar in sheltered locations at tree-line. Sun crusts, surface faceting and wind effect on various aspects in the alpine. 15-40 cm of snow lies over the Nov 27th and Nov 23rd crusts. Both of these now overlie the Halloween crust/facet layer that sits 30-50cm above the ground.
Avalanche Summary
During the last few days with inverted temperatures yielding above freezing conditions treeline and above, only a few very small loose wet avalanches in the alpine were observed. These were in steep rocky terrain that was in the sun, and sheltered from the wind. Where observed, these did not triggered any deeper weaknesses.
Confidence
Problems
Persistent Slabs
Some uncertainty for triggering various mid-pack layers remain, but we have come through a warm period and a lot of skier testing produced no activity over the past five days. These slabs still deserve respect in steep and shallow areas.
Be aware of thin areas that may propogate to deeper instabilites.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Dec 12th, 2017 4:00PM
