Avalanche Forecast
Issued: Dec 3rd, 2017 8:03AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
ian gale,
Parks Canada
The storm slab will be most reactive at ridgetop where exposed to wind. Avoid exposure to other groups above or below you.
Summary
Weather Forecast
A ridge of high pressure will build today over Roger's Pass. Expect cloudy skies with some sunny breaks throughout the day today. No new snow is forecast and the alpine high will be -10 with the freezing level staying at valley bottom. Winds will be generally light from the Northwest. The high pressure will dominate the weather through the week
Snowpack Summary
25cm of recent snow sits on the previous settled storm snow. The November 26/23rd crust layers are easily identified down 65-80cm. Recent stability tests show a generally good bond between the Nov 26 and the dry snow above. The lower snowpack is still moist but is starting to dry out with cooler temperatures.
Avalanche Summary
The storm from Friday and Saturday brought heavy snowfall and strong winds at ridgetop. This triggered a natural avalanche cycle to size 3 with some paths running to valley bottom. Friday the avalanche path 'Frequent Flyer' ran during the day, burying the skintrack 7-10m wide. A good report here.
Confidence
Problems
Storm Slabs
Settling new snow and wind at ridgetop has created a reactive soft slab. Compression tests yesterday showed shears in the storm snow down 15 & 30cm. In steep alpine terrain avalanches may run to the bottom of run-outs. Be aware of overhead exposure!
Evaluate unsupported slopes critically.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 4th, 2017 8:00AM
