Avalanche Forecast

Issued: Jan 5th, 2013 9:45AM

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

Avalanche Canada jfloyer, Avalanche Canada

Summary

Confidence

Fair - Intensity of incoming weather is uncertain

Weather Forecast

Sunday: Mostly dry. Treeline temperatures around -4C. Winds mostly light southwesterly. Monday: 20-30 cm new snow. Temperatures around -6C. Strong southwesterly winds gusting to 60 km/h. Tuesday: Moderate or heavy snowfall with temperatures around -8C. Moderate or strong southwesterly winds.

Avalanche Summary

A cycle of natural and human-triggered (including remotely-triggered and helicopter-remote) avalanches of up to size 2.5 has been observed across the region. This pattern is ongoing. Storm snow is propagating easily on buried surface hoar and facets. Skiers recently triggered avalanches that resulted in wide propagation in the Shames Backcountry, highlighting the surprising reactivity of the snowpack.

Snowpack Summary

30-70cm of recent storm snow is bonding very poorly, with very touchy reactivity on buried surface hoar, especially near Terrace. This layer is being triggered naturally or remotely and propagating widely. Recent strong southwesterly to southeasterly winds have set up wind slabs in many exposed lee areas. There are two surface hoar layers in the upper snowpack. The upper one formed at the end of December and is buried approximately 30 cm below the surface. This one is particularly reactive at present. The lower one formed at the beginning of December and is buried approximately 90 cm below the surface. Hard, planar compression tests have been reported on this layer. Near the base of the snowpack, a crust/facet layer continues to give hard, sudden results to no results in snowpack tests. This weakness is unlikely to be triggered by a single person, but it remains possible with a very heavy load (e.g. cornice fall) or from a thin-spot trigger point.

Problems

Storm Slabs

An icon showing Storm Slabs
Storm snow is bonding poorly with buried surface hoar, creating a very touchy storm slab problem. �A person may trigger large avalanches easily, or even from a distance. Wind slabs are also likely to be found behind ridges, ribs and gully walls.
Note recent avalanche activity.>Avoid freshly wind loaded features.>Start on small terrain and use safe slope-cutting techniques to cut the top of slopes before riding them.>Enter your line well below ridge crests to avoid wind loaded pillows.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 5

Valid until: Jan 6th, 2013 2:00PM