Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Dec 2nd, 2012–Dec 3rd, 2012

Alpine
Natural and human triggered avalanches likely.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural and human triggered avalanches likely.
Treeline
Natural and human triggered avalanches likely.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.

Regions

Kootenay Boundary.

Confidence

Poor - Due to limited field observations

Weather Forecast

Synopsis: A broad and persistent trough of low pressure of the coast of BC will maintain a westerly-southwesterly flow with mild and wet conditions for the next few days. A strong frontal system should move across southern BC on Tuesday bringing heavier precipitation and rising freezing levels. Monday: Light to moderate snowfall – 10-15 cm; the freezing level is around 1000-1200 m; winds are light to moderate from the southwest. Tuesday: Heavy snow – 35-45 cm; the freezing level could jump to 1800-2000 m; winds are strong from the southwest. Wednesday: Cloudy with flurries; the freezing level lowers to 600-800 m.  

Avalanche Summary

Several natural and human triggered avalanches up to size 2 were reported in the Kootenay Pass area on Friday and Saturday. Most of these avalanches involved the recent moist storm snow. The size and likelihood of natural and human triggering avalanches should increase with continued precipitation over the next couple days. If you and your friends have been out exploring and riding in the backcountry and have some observations to share please send an email to [email protected].

Snowpack Summary

Up to 70 cm of moist storm snow has fallen in the past 3 days. This snowfall was accompanied by generally moderate southerly winds, forming wind slabs in exposed leeward terrain. Below the storm snow is a layer of surface hoar or a thin crust. Recent snowpack tests give consistent easy results on this layer.In the mid snowpack, there may be a thin buried surface hoar layer between 80 and 100cm deep. At the base of the snowpack sits the early November rain crust. This layer seems most likely to be found in deeper snowpack areas and may have associated facets. These layers have been unreactive in recent days, but may have the potential to 'wake-up' with continued loading and forecast warming.In general, snowpack data is sparse in this region and significant variations likely exist from one drainage to another. In short, digging down and making your own observations will be critical to safe slope selection. Any observations from the field are welcome at [email protected].

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.