Avalanche Forecast

Issued: Apr 2nd, 2015 9:04AM

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.

ccampbell, Avalanche Canada

South Coast.

Deep persistent weaknesses are still producing avalanches. Big alpine features cannot be trusted.

Summary

Confidence

Good

Weather Forecast

Around 5 cm of snow is expected Friday afternoon through to Saturday morning, before things start to dry out with a mix of sun and cloud on Sunday. Daytime high freezing levels are expected to hover around 1600 m for the forecast period. Moderate southwesterly alpine winds are expected on Friday then light but gusty southwesterlies for Saturday before shifting to southeasterlies on Sunday.

Avalanche Summary

Over the past few days, several natural cornice falls and wind slab avalanches to Size 2 were observed in the north of the region. Two of of the larger avalanches possibly stepped-down to the mid-March persistent weakness on north facing alpine slopes. Also reported were several loose sluffs to Size 1.5 in response to sun-exposure on south aspects.

Snowpack Summary

20-30 cm of low density storm snow is sitting on a strong and supportive rain crust buried last Saturday that extends as high as 2100m. West through southwesterly winds have shifted these new accumulations into touchy wind slabs in exposed terrain. A facet/crust persistent weakness buried mid-March is down approximately 50-100 cm and recently produced moderate sudden results in snowpack tests where it was found down 55 cm near the Duffey Lake Road. This remains the chief concern amongst avalanche professionals in the region due to it's potential for very large avalanches.

Problems

Persistent Slabs

A cautious approach is still required because, although it would likely take just the right trigger in just the right spot, avalanches failing at this interface may not be survivable.

Avoid convexities or areas with a thin or variable snowpack.>Be aware of thin areas that may propogate to deeper instabilites.>Be aware of the potential for large, deep avalanches.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 5

Storm Slabs

Be alert to conditions that change with elevation.>Use ridges or ribs to avoid pockets of wind loaded snow.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Apr 3rd, 2015 2:00PM