Avalanche Forecast
Issued: Dec 1st, 2017 4:41PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
mgrist,
Avalanche Canada
This forecast is based on very few field observations and a high level of uncertainty exists. A conservative approach to terrain selection is critical until more snowpack data becomes available.
Summary
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Modest snowfall Friday overnight to Saturday (10-15 cm possible), followed by a clearing trend and fine weather by early next week. Saturday: Isolated flurries / Light to moderate south winds / Freezing level at 1000mSunday: Cloudy with sunny breaks / Light and variable winds / Freezing level at 800mMonday: A mix of sun and cloud / Moderate northerly winds / Freezing level at surface / Alpine highs of -8 Celsius
Avalanche Summary
On Thursday we had a report of a skier-triggered Size 1 storm slab at 2000m on a north west aspect near Nelson. See here for the MIN report. The recent storm snow has been reactive to ski cutting, especially lee features which have seen wind loading.On Tuesday a naturally-triggered size 1 storm slab was observed around Kootenay Pass. The avalanche occurred on a southeast aspect at about 2100m, and is thought to have failed on the recently buried crust. A natural storm slab avalanche cycle is expected in response to recent wind and snowfall. The possibility of human triggering these storm slabs may continue into the weekend.We currently have very limited observations in this region. Please submit your observations to the Mountain Information Network (MIN).
Snowpack Summary
20 - 40cm of new snow has fallen in the past week. At higher elevations, south through west winds (gusting strong at times) redistributed the new snow, forming wind slabs on lee features.Below the recent storm snow you'll likely find a couple of widespread crusts which formed as a result of last week's rain. Late November's rain really shrunk the snowpack and has transitioned much of the snowpack from dry to moist snow. The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 100-170cm in the alpine, 50-100cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.
Problems
Storm Slabs
Recent wind and snowfall has likely formed touchy new storm slabs. Storm slabs may be more reactive in heavily wind-exposed terrain, or in areas where the new snow has a weak bond with underlying crusts.
The new snow may require several days to settle and stabilize.Be cautious as you transition into wind affected terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 2nd, 2017 2:00PM
