Avalanche Forecast
Issued: Dec 3rd, 2018 5:09PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
ghelgeson,
Avalanche Canada
Travel is RUGGED. Watch for the formation of fresh wind slabs up high. It's unlikely, but it may be possible to trigger a large avalanche in steep, smooth, alpine bowls where a dense slab rests on a weak base.
Summary
Confidence
Low - Due to the number of field observations
Weather Forecast
The high amplitude ridge sitting off the BC Coast is expected to deflect any potential storm systems away from the province this week. The forecast period is marked by cooler temps, clear skies and no significant precipitation with no change expected for the foreseeable future.MONDAY NIGHT: Freezing level at valley bottom, light northwest wind at most elevations, moderate northwest wind at ridgetop, no significant precipitation expected. TUESDAY: Scattered cloud cover, freezing level at valley bottom, light southerly wind at most elevations, strong northwest wind at ridgetop, no significant precipitation expected. WEDNESDAY: Mostly clear sky, freezing level at valley bottom, light variable wind, no significant precipitation expected. THURSDAY: Clear sky, freezing level at valley bottom, light variable wind, no significant precipitation expected.
Avalanche Summary
No new avalanches have been reported in the region. Natural avalanche activity is unlikely, but its possible to trigger pockets of wind slab from leeward terrain features. If you have been out, please submit any observations to the Mountain Information Network MIN.
Snowpack Summary
The region received up to 20 cm of snow over the past week. Isolated pockets of stiff wind slab may exist on leeward slopes. Below the surface exists a series of crusts and a feathery surface hoar layer. We have a lot of uncertainty around the weak surface hoar layer and its distribution. I suspect it could exist on sheltered slopes in the alpine and at treeline. A mixed layer of melt-freeze crusts and sugary facets buried late October can be found at the base of the snowpack at treeline and in the alpine. This layer has not been active, but there is potential for slab avalanches on this layer given the current snowpack structure. Terrain features like smooth alpine bowls with variable snowpack depths would be most suspect.Average snowpack depths at treeline are near 50 cm and taper quickly as elevation decreases. Snow depths below tree line are generally below the threshold depth to produce avalanche.
Problems
Wind Slabs
Although there is not a lot of fresh snow, strong wind Monday night and Tuesday may create fresh wind slabs. These would hide old wind slabs that may remain sensitive to human triggering both immediately lee of ridgecrest and in extreme terrain.
If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Increase your caution as you transition into wind affected terrain.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 4th, 2018 2:00PM
