Avalanche Forecast
Regions: North Columbia.
Riding quality is good, but wind slabs are sensitive to human triggering at and above treeline to size 2. Below treeline the new snow rests on a touchy layer of surface hoar, so steep unsupported features, rolls, creek bottoms & terrain traps are all suspect.
Confidence
Low - Uncertainty is due to the limited number of field observations.
Weather Forecast
After a stormy weekend we’re transitioning to clearing skies, colder temperatures and no significant precipitation for the foreseeable future.
MONDAY NIGHT: Freezing level at valley bottom, light variable breeze, no significant precipitation expected.
TUESDAY: Scattered cloud cover, freezing level at valley bottom, light east/northeast wind, no significant precipitation expected.
WEDNESDAY: Scattered cloud cover, freezing level at valley bottom, light to moderate east/northeast wind, no significant precipitation expected.
THURSDAY: Clear skies, freezing level at valley bottom, light east wind, no significant precipitation expected.
Avalanche Summary
Observations are lean right now, but the weekend snow combined with wind out of the south & southwest to form wind slabs near ridge crest that have been sensitive to human triggering up to size 1.5. This MIN post has a great photo that is pretty representative to what we're envisioning. If you've been out recently please let us know what you're seeing on the MIN. We're particularly interested in learning how widespread and sensitive the wind slab problem is. Thanks!
Snowpack Summary
Winter is slowly descending to the valleys with the snowline around 1200 m across the region. Total snowpack depths range from about 80 cm below treeline to as high as 180 cm in the alpine.
The weekend storm produced 20 to 35 cm of snow accompanied by strong west/southwest wind. On steep south facing slopes in the alpine the new snow rests on a crust. A crust is also present on all aspects below 1600 m and many locations have surface hoar on top of the crust.
Crusts that formed in late October are now buried 50 to 100 cm deep. We're working off of a short list of observations, but this late October crust layer is highly variable and may be associated with both surface hoar and facets. This is a layer to watch over the next week as unlimited visibility and good travel conditions begin to sing the Alpine's siren song.
Avalanche Problems
Storm Slabs
Last weekend's storm produced 20 to 35 cm of snow accompanied by strong west/southwest wind forming widespread storm slabs. These slabs rest on a variety of weak layers which will likely keep them susceptible to human triggering this week, especially in bigger terrain near ridge crest. Caution below treeline too, although it's pretty shallow down there new snow may be resting on surface hoar.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 2.5