Avalanche Forecast

Issued: Nov 29th, 2012 9:31AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Storm Slabs and Persistent Slabs.

jlammers, Avalanche Canada

Kootenay Boundary.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain

Weather Forecast

Friday: Moderate snowfall / Moderate southwest winds / Freezing level at 1500mSaturday: Moderate snowfall / Moderate southerly winds / Freezing level at 1500mSunday: Light snowfall / Light southeast winds / Freezing level at 1300m

Avalanche Summary

No new avalanches have been reported. 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 forecaster@avalanche.ca.

Snowpack Summary

Light amounts of new snow fell in the region on Wednesday night. Forecast wind and snow will add to the size and reactivity of this developing slab which sits upon a variety of surfaces which may include weak surface hoar crystals, a sun crust on steep solar aspects, and well settled storm snow from last week.In the mid snowpack there may be a spotty, thin buried surface hoar layer between 50 and 80cm down. At the base of the snowpack sits the early November rain crust. Located about 100cm below the surface, it seems most likely to be found in deeper snowpack parts of the region and may have associated facets. These layers seem to have been unreactive in recent days, but may have the potential to 'wake-up' with forecast loading.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 forecaster@avalanche.ca.

Problems

Storm Slabs

Forecast wind and snow will add to the size and reactivity of the storm/ windslab that formed on Wednesday evening. This developing avalanche problem may override a variety of potentially weak surfaces such as sun crusts and surface hoar.

Use extra caution during periods of heavy loading from new snow and wind.>

Aspects: North, North East, East, South East, South, South West.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Persistent Slabs

Although the likelihood of a release is low, the consequences of a persistent slab release could be significant. These layers may wake-up with additional loading.

Choose well supported terrain without convexities.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Valid until: Nov 30th, 2012 2:00PM