Avalanche Forecast

Issued: Feb 26th, 2013 9:52AM

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

ccampbell, Avalanche Canada

South Coast.

Summary

Confidence

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

Weather Forecast

Wednesday: Light flurries with another 3-5cm throughout the day, light to moderate southwesterly winds and freezing levels as high as 1200-1400m. Thursday: Continued light flurries before a warm and wet frontal system makes landfall sometime in the afternoon. Friday: Moderate to heavy snowfall, particularly in the Coquihalla area, with strong southwesterly winds and freezing levels as high as 2000m.

Avalanche Summary

Recent reports include numerous Size 1.0-2.5 natural dry loose and soft wind slab avalanches throughout the region.

Snowpack Summary

Light snowfall on the Duffey and heavy snowfall on the Coquihalla has been redistributed into wind slabs at treeline and above. Surface hoar, facets, and/or crust buried early last week is now around 70cm deep, depending on the area, and remains particularly touchy at treeline. Fresh wind slabs, buried wind slabs, and recent storm snow weaknesses within the top metre are highly reactive to human triggers and have the potential to step down to this persistent weakness, or deeper to another persistent weaknesses buried earlier in the month. Cornices are also large and unstable.

Problems

Storm Slabs

New and recent storm snow is expected to become very touchy with continuous loading throughout the forecast period, especially where wind-loaded. Thinner slabs failing within the recent storm snow may step down to old snow surfaces from last week.

Choose well supported terrain without convexities.>Be cautious as you transition into wind affected terrain.>Avoid freshly wind loaded features.>Give cornices a wide berth when travelling on or below ridges.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 5

Persistent Slabs

An assortment of persistent weaknesses lurk in the top 100cm. Most notably is surface hoar buried early last week as well as the week before, which are most concerning in sheltered treeline areas.

Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>Remote triggering is a concern, watch out for adjacent slopes.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 4

Valid until: Feb 27th, 2013 2:00PM