Avalanche Forecast
Issued: Dec 6th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Deep Persistent Slabs.
dsaly,
Avalanche Canada
Keep an eye out for rogue pockets of wind slab. Getting knocked off your feet can be serious in extreme terrain.
Summary
Confidence
Moderate - Uncertainty is due to the limited number of field observations.
Weather Forecast
SUNDAY NIGHT: Patchy clouds / Light, southwest ridgetop wind / alpine low temperature -7 / Freezing level valley bottom
MONDAY: Partly cloudy with isolated flurries / Light to moderate, southwest ridgetop wind / alpine high temperature -3 / Freezing level 1200 m, light inversion
TUESDAY: Cloudy with scattered flurries, 5-10 cm / Light, gusty southwest ridgetop wind / alpine high temperature -4 / Freezing level 1100 m
WEDNESDAY: Cloudy with scattered flurries, 5-10 cm / Light, gusty southwest ridgetop wind / alpine high temperature -4 / Freezing level 1000 m
Avalanche Summary
Outside of a few small loose-wet avalanches from steep terrain, there have been no avalanche observations since last Wednesday (Nov 2) when numerous wet loose avalanches were reported from NE slopes above 2000 m, likely triggered by warming.
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 melt-freeze crust covers most solar slopes and a variety of wind-affected surfaces around found on more polar slopes at treeline and above. Widespread surface hoar growth has been observed around the region. The snowpack is well settled below. Snowpack depths vary with elevation, treeline averages between 50-100 cm.Â
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.
Terrain and Travel
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
- Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
- Small avalanches can have serious consequences in extreme terrain. Carefully evaluate your line for wind slab hazard before you commit to it.
Problems
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 so we're keeping it on our radar for now. While it's been showing some results in snowpack tests in some areas, 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 7th, 2020 4:00PM
