Avalanche Forecast

Issued: Mar 7th, 2013 9:18AM

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

Avalanche Canada triley, Avalanche Canada

Summary

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Friday

Weather Forecast

Overnight and Friday: Some clouds and moisture are expected to linger in the region as the low pressure system to the South moves Eastward. The freezing level should rise to about 1200 metres.Saturday: The ridge of high pressure is expected to re-build over most of the interior ranges, bringing mostly clear skies and light winds.Sunday: The low pressure system moving in from the Pacific is expected to be mostly confined to the coast, but some models show a pulse of moisture moving into the interior.

Avalanche Summary

Some sluffing was reported from steep terrain in the alpine. There was a report from the Central Selkirks of a chunk of snow that fell out of some cliffy terrain at treeline and then propagated three progressively deeper slabs resulting in a size 2.5 avalanche sliding on the February 12th weak layer down about 100 cms.

Snowpack Summary

A light dusting of new snow is sitting above various sun crusts and old storm slabs. The storm slab continues to settle, and is becoming more stubborn to trigger. The weak layer of surface hoar that was buried on February 12th is now down about 100-150 cms and continues to be triggered by light additional loads on Southerly aspects where it is sitting on an old sun crust. Larger loads like cornice fall or explosives have been able to trigger this layer on various aspects in the alpine and at treeline. If the we get a period of strong solar radiation, then we may see another cycle of natural activity on Southerly aspects resulting in large destructive avalanches.

Problems

Persistent Slabs

An icon showing Persistent Slabs
There is a weak layer of buried surface hoar down about 100-150 cms that may be triggered by large loads like re-grouping, cornice fall, or smaller avalanches in motion. Strong solar radiation may initiate this layer where it sits on a crust.
Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

4 - 7

Storm Slabs

An icon showing Storm Slabs
The storm snow is settling and bonding, but may continue to be triggered by human activity. Periods of strong solar radiation may cause a cycle of storm snow releases on Southerly aspects.
The new snow will require several days to settle and stabilize.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

3 - 6

Valid until: Mar 8th, 2013 2:00PM