Avalanche Forecast
Issued: Dec 18th, 2019 8:17AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Dry.
ross campbell,
Parks Canada
Another good day for conservative terrain choices! We are in a extended period of elevated hazard, the snowpack will need more time to settle and stabilize.
Summary
Weather Forecast
Snow easing to flurries today, temperatures in the alpine should hover around -6, and winds are forecasted to stay light to moderate from the South. Flurries continue overnight into Thursday, with accumulations up to 7cm. The main weather story is Friday/Saturday, each day receiving a foot of snow, strong winds and rising temperatures!
Snowpack Summary
50-60cm of new snow now buries the Dec 11 surface hoar layer. New snow, Moderate winds built storm slabs at all elevations. The Nov 23rd surface hoar/crust/facet combo is down +/-100cm (SH is most prevalent in sheltered treeline locations) but has become increasingly stubborn in testing. The mid-lower snowpack is settled and strong.
Avalanche Summary
Yesterday's natural avalanche cycle tapered off slightly last evening. The cycle produced avalanches to size 3-3.5 traveling far and fast, reaching valley bottom and dusting up-tracks and the road. The number of natural avalanches will decrease compared to yesterday; however, the size and destructive potential has increased with the added load!
Confidence
Problems
Storm Slabs
Storm slabs are primed for human-triggering on steep unsupported terrain features. Storm slabs overlie the Dec 11th surface hoar layer, which can be found 50-60cm below the surface.
- Watch for fresh storm slabs on exposed lee slopes at and above treeline.
- Use conservative route selection, choose moderate angled and supported terrain with low consequence.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Dry
Surface snow will be prone to sluffing, especially on steep, unsupported terrain features. Sluffs are running fast and far, picking up more snow as it flows down gullies.
- Be aware of party members below you that may be exposed to your sluffs.
- Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 19th, 2019 8:00AM
