Avalanche Forecast

Issued: Jan 27th, 2015 9:29AM

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

jlammers, Avalanche Canada

South Coast.

Observations from the high alpine (above 2300m) have been very limited. Dig down and test for weak layers before committing to steeper, exposed lines.

Summary

Confidence

Good

Weather Forecast

Expect a mix of of sun and cloud for the forecast period. Winds are forecast to remain light to moderate from the northwest, switching to southwest on Thursday and Friday. Freezing levels should hover at 1200m on Wednesday, rise to 1800m on Thursday, and fall back to 1200m on Friday.

Avalanche Summary

On Monday, a size 2 persistent slab avalanche was remotely triggered from a distance of about 100m in the far north of the region (Goldbridge area).Â The avalanche occurred at about 2300m in a wind-loaded area and failed on surface hoar buried about 70cm below the surface. The remote triggering points to the touchy nature of the instability in this area. No other avalanches were reported.

Snowpack Summary

Up to 50 cm of settled storm snow has been saturated by rain up to about 2100m. With more recent cooling, most surfaces will now be refrozen. At the highest elevations you might find dense, stubborn wind slabs in lee terrain. New cornice development has also been noted. The older storm snow overlies a hard crust and/or surface hoar layer which formed in early January. The bond at this interface will be largely elevation dependant as rain may have penetrated the snowpack enough to dissolve the crust in many areas. In the north of the region, snowpack tests indicate this interface is still sensitive to triggering in some areas.Deeper snowpack weaknesses seem to have become unreactive, and should become even less of a concern if the forecast cooling trend verifies.

Problems

Cornices

With recent cooling, large and fragile cornices have likely gained strength. I'd still give them a wide berth, and use extra caution if the sun comes out.

Give cornices a wide berth when travelling on or below ridges.>

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Persistent Slabs

A recent large avalanche shows that persistent weak layers, buried up to 70cm below the surface, should still be on our radar in high elevation terrain in the north of the region.

Be alert to conditions that change with elevation.>Dig down to find and test weak layers before committing to a line, especially in the north of the region.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Jan 28th, 2015 2:00PM