Avalanche Forecast

Issued: Jan 19th, 2016 8:33AM

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

pgoddard, Avalanche Canada

Cariboos.

Conditions are variable across the region. Investigate your local snowpack before committing to a line.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

A few flurries are possible on Wednesday ahead of a light brushing from some Pacific storms on Thursday and Friday. Around 5 cm of snow is expected each day, with moderate to strong SW winds and the freezing level rising to around 1600 m.For more details check out http://www.avalanche.ca/weather.

Avalanche Summary

On Monday, several size 1-1.5 persistent slabs were triggered by skiers directly, or remotely from a distance. These were between 1300 and 2100 m. A size 2.5 avalanche also failed naturally on a NW aspect at 2200 m. Skiers also reported whumpfing and shooting cracks at low elevations. In many areas, the persistent slab is just a developing problem, while in some spots there is already a deeper or more cohesive slab. We had a recent report from the Wells Grey area of a skier remotely triggering a size 2 avalanche that was 35 cm deep from 20 m away. This avalanche was 80 m wide and released on buried surface hoar in the alpine. This group also reported numerous whumpfs during the day.

Snowpack Summary

20-50 cm of recent storm snow has formed a reactive slab over a volatile layer of buried surface hoar in some places. The buried surface hoar may be most prevalent at and below treeline. The slab is likely to be especially reactive where it has gained cohesion through wind pressing, warming, and/or settlement. In general, the mid and lower snowpack are strong with any weak layers considered dormant for now. Snowpack depths are variable and shallow snowpack areas may have weak facetted crystals near the ground.

Problems

Persistent Slabs

In some parts of the region, the slab sitting over a volatile weak layer is primed for human triggering. It has been most reactive at and below treeline.

Extra caution required in open terrain features at and below treeline.>Use conservative route selection.>Avoid steep open slopes and convex rolls at and below treeline where buried surface hoar may be well preserved.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 4

Wind Slabs

Recently formed wind slabs may be lurking behind ridges and ribs.

Avoid lee and cross-loaded terrain near ridge crests.>Travel on ridgetops to avoid wind slabs on slopes below.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Jan 20th, 2016 2:00PM