Avalanche Forecast
Issued: Dec 24th, 2011 9:01AM
The alpine rating is Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
Sunday: Light to moderate snowfall through the day, with the freezing level near 1000m. Strong south-westerly winds at ridgetop. Storm snow totals should reach around 15cm on average by Sunday, with local variations. Expect enhanced amounts on the western side of the range.Monday: Moderate precipitation at times, with the freezing level slowly rising to 1200m. Moderate-strong south-westerly winds.Tuesday: Confidence for Tuesday's weather is limited, but we're currently expecting moderate snowfall at times, with a rising freezing level.
Avalanche Summary
No new avalanches have been reported since Wednesday. It's a big area, however, and we receive limited reports. Earlier in the week, a natural avalanche cycle was observed in the South Cariboos, mostly on north aspects in the alpine. Several rider-triggered avalanches occurred, with the mid-December hoar/facet/crust interface causing most concern. With new storm slabs and wind-slabs building over these known weaknesses, further avalanche activity remains a distinct possibility.
Snowpack Summary
Recent storm snow continues to be redistributed by southwest winds. Wind slabs with the potential to propagate widely exist in the alpine, particularly on north through east aspects. At treeline and below, pockets of wind slab also exist in open areas. A surface hoar/facet/crust interface is buried anywhere from 30- 80cm deep and has recently proven itself to be variable in its distribution, with concerning (sudden planar) results in snowpack tests and rider-triggered avalanches in some places and little results in other places. This means the problem is somewhat spotty, but could be lurking round the corner - and have huge consequences if triggered.A resistant-type shear about 30cm down within the recent storm snow also exists. A sun crust also exists in the alpine on steep south and west aspects. The mid-pack is generally strong and well settled.
Problems
Wind Slabs
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 25th, 2011 8:00AM