Avalanche Forecast
Issued: Dec 5th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Loose Dry.
CG,
Avalanche Canada
The Nov 17th persistent weak layer (surface hoar/facets/crust) is well within the range of human triggering. Assess the snowpack carefully before stepping out into large open slopes, especially around treeline.
Dry, loose avalanches may pose a problem in steep, confined terrain if more snow (>10cm) falls than forecasted.
Summary
Confidence
Moderate
Avalanche Summary
On Sunday several sz 1-1.5 solar-induced loose dry avalanches occurred within the surface facet layer out of steep, rocky terrain. On Saturday Lone Pine produced a size 2 glide crack release which ran into the fan.
Whumpfing and remote-triggering continues on small, unsupported pillows below tree line on the Nov 17 persistent slab, both in GNP and adjacent to the region.
Snowpack Summary
Light fluff is falling onto a sugary, faceted surface. The Nov 17 persistent slab (surface hoar 5-30mm, facets, and crust) is down 50-80cm with the largest surface hoar present on sheltered slopes at treeline and below.
Snowpack depth is still variable (~120cm at treeline); early season hazards remain a concern.
Weather Summary
Cloud is spreading across the region, bringing 5-10cm of low-density snow and moderate West winds at ridgetop. Temps remain cool, with an Alp high of -13*C.
Continuing flurries, cool temps, and moderate SW winds prevail Wed/Thurs.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Loose avalanches may start small but they can grow and push you into dangerous terrain.
Problems
Persistent Slabs
The Nov 17 surface hoar is down 50-80cm and most prevalent around tree line. The surface hoar continues to give 'sudden' results in snowpack tests.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Loose Dry
10cm of dry, low-density snow is forecasted to land on top of a faceted surface. Expect fast sluffing in steep, confined terrain, potentially digging deeper into the facets and accumulating enough mass to bury a person.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 6th, 2022 4:00PM
