Avalanche Forecast
Issued: Dec 9th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Deep Persistent Slabs.
dsaly,
Avalanche Canada
A localized pulse dropped moist snow with moderate winds. Investigate the bond of new snow and older surfaces - in some areas it sits on a crust, and other areas possibly surface hoar.
Summary
Confidence
Weather Forecast
WEDNESDAY NIGHT: Cloudy with isolated flurries, trace to 5 cm / Light variable ridgetop wind / alpine high temperature -4 / Freezing level falling to valley bottom
THURSDAY: Partly cloudy / Light southeast ridgetop wind / alpine high temperature -5 / Freezing level valley bottom
FRIDAY: Sun and cloud / Light south ridgetop wind / alpine high temperature -6 / Freezing level valley bottom
SATURDAY: Sunny breaks / Light southwest ridgetop wind / alpine high temperature -6 / Freezing level valley bottom
Avalanche Summary
There have been no recent avalanche observations.
Other than a few small loose-wet avalanches from steep terrain on the last few sunny days, the last avalanche observations were Wednesday Dec 2 when warming likely triggered numerous wet loose avalanches from NE slopes above 2000 m.
Have you been out and about in the mountains? If so please submit to the Mountain Information Network (MIN). It doesn't have to be technical it can be as simple as a photo. Photos are especially helpful! Sending a big thank you to the already submitted MIN's this season!
Snowpack Summary
A localized band of moisture and wind deposited up to 20 cm above 1800 m and may overlie a thin crust which developed in areas that received rain or heavy mist before falling temperatures and snowy precipitation.
Warm temperatures moistened the snowpack above 2000 m. At upper (drier) elevations, new snow covers old surfaces of crusts on most slopes, wind-polished and dry, faceted snow on northerly aspects, and a possible layer surface hoar. Early in the week surface hoar developed around the region, and may be especially large in sheltered treeline areas, however in areas where a thin rain crust formed, its likely the wet precipitation crushed the surface hoar.
Crusts from mid-and early-November are generally found 30 cm below the snow surface and 10 cm up from the ground at all elevations. While they are showing resistant planar results in snowpack tests, a lot of uncertainty still exists with limited observations and while we don't think they're currently a problem, we're not ready to throw them out yet.
Snowpack depths vary with elevation, treeline averages between 50-100 cm.
Terrain and Travel
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Closely monitor how the new snow is bonding to the old surface.
- Investigate the bond of the recent snow before committing to your line.
Problems
Storm Slabs
Up to 20 cm fresh snow accumulated (in localized areas) with moderate winds. In some areas it sits over a rain crust, and other areas possibly surface hoar. This problem is likely confined to ridgelines and alpine features.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
A crust exists near the base of the snowpack, and weak, sugary facets have been observed over this crust. We have a lack of decisive data on this layer - it's been showing some results in snowpack tests in some areas, and most reports describe an improving bond to the overlying snow. Although we don't think it presents a problem, without more information we're reluctant to throw it out. The most likely trigger spots are terrain areas with smooth ground cover such as scree slopes, grassy slopes, or rock slabs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 10th, 2020 4:00PM
