Avalanche Forecast

Issued: Jan 13th, 2016 8:21AM

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

Avalanche Canada triley, Avalanche Canada

Incremental storm snow may be settling into a cohesive slab above buried weak layers, allowing for longer fractures and resulting in larger avalanches. Wind loaded pockets may be deep and easily triggered.

Summary

Confidence

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

Weather Forecast

Another 5-10 cm of new snow combined with moderate southwest winds overnight as the freezing levels drop back to valley bottoms. Flurries or periods of light snow on Thursday combined with moderate northwest winds and alpine temperatures around -5. Some flurries expected on Friday with a chance of broken skies in the afternoon; winds light southwest and alpine temperatures around -10. Increasing southwest winds on Saturday with increased cloud and some flurries or light snow.

Avalanche Summary

Storm slab avalanche up to size 3.0 in the Rogers Pass today. Other operations have reported mostly size 1.5 natural avalanches. One report from the southern Monashees of skier remotely triggering a storm slab about 50 cm deep above surface hoar in a cut block at 1600 metres elevation. Numerous avalanches were reported on Tuesday up to size 2.0 but mostly size 1.0-1.5 that were releasing as storm slabs or loose dry avalanches. Expect storm slabs to continue to be easy to trigger on Thursday. Pockets of wind transported snow may be deep and propagate where they are sitting on weak buried crystals and/or old melt-freeze crusts.

Snowpack Summary

Another 10-15 cm of new snow has combined with recent snow to make storm snow totals of 20-40 cm. Some areas have reported a thin freezing drizzle crust on the surface before the Wednesday morning snow arrived. Storm slabs now overlie a variety of touchy weak layers. Storm and wind slabs will likely continue to build with forecast snow overnight. There is about 50 cm above the surface hoar, facets, and sun crusts that were buried early in January. The mid and lower snowpack are generally well settled and strong.

Problems

Storm Slabs

An icon showing Storm Slabs
Forecast new snow and wind are expected to continue to develop storm slabs at all elevations. Storm slabs may be sitting on buried weak layers, allowing for long fracture propagations in areas where the storm snow has settled into a cohesive slab.
Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Jan 14th, 2016 2:00PM