Avalanche Forecast
Issued: Dec 12th, 2016 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Dry and Deep Persistent Slabs.
grant statham,
Avalanche Canada
The valley bottom snowpack in Little Yoho remains shallow, so any skiing at Emerald Lake or Mt. Field will need to content with the bushes at low elevations - but higher up is probably quite good. Look here to see the developing faceted snowpack.
Summary
Weather Forecast
Severe clear and cold for the week - with a brief burst of snowfall on Thursday as the edge of the arctic air moves through town and back again. Expect Tuesday's temperatures to range from -15 to -25 and some forecasts are showing NW winds rising in alpine areas. Look for sunny, sheltered locations to stay warm - its really cold out there!
Snowpack Summary
5 cm of new snow overlies a mostly facetted snowpack that is growing weaker each day with these cold temperatures. Profiles today near Sunshine Village showed loose facets in the upper 30 cm, which have no cohesion and are creating the Loose Dry problem. Also 40 cm above the ground is the Nov 12 crust, also growing weaker each day.
Avalanche Summary
No significant slab avalanches reported or observed in the past 5 days, but loose dry skier triggered avalanches in steep terrain have been reported in several locations over the past few days. This is a result of the surface faceting that is occurring under these cold temperatures as the surface snow weakens and looses cohesion.
Confidence
Problems
Loose Dry
The surface snow is faceting rapidly and becoming weak, resulting in large sluffs developing in steep and/or confined terrain. Be very wary of your exposure above and below, and remember to ski off fall line to manage any sluffs growing behind you.
- Be aware of party members below you that may be exposed to your sluffs.
- On steep slopes, pull over periodically or cut into a new line to manage sluffing.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
The Nov 12 crust has weak snow all around it, and is a suspect and dangerous layer. Although it's reactivity seems to have abated during the current cold snap, we expect it to awaken again with additional load and warmer temperatures (one-day).
- Avoid shallow snowpack areas where triggering is more likely.
Aspects: North, North East, East.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Dec 13th, 2016 4:00PM
