Avalanche Forecast

Issued: Jan 4th, 2016 7:44AM

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

triley, Avalanche Canada

Purcells.

Buried surface hoar from mid December continues to be a concern in parts of the region. Dig down to identify if this is a concern in your area.

Summary

Confidence

High

Weather Forecast

Overcast with freezing levels at valley bottoms for the duration of the forecast. Light south or southeast winds and alpine temperatures around -7 during the days. Some flurries or light snow falls with little accumulation expected. The south of the region may see a bit more snow, but probably total snowfall of 5-10 cm.

Avalanche Summary

Some loose snow avalanches continue to be reported from steep alpine terrain. Last week several large avalanches were skier triggered in the southern Purcells, west of Kimberly, on buried surface hoar. Something to keep in mind when looking for new lines!

Snowpack Summary

Conditions are quite variable throughout the region. In the southern Purcells, (west of Kimberley), a prominent layer of buried surface hoar has shown to be reactive to human triggers. In this part of the region, it's buried down 40 cm with a cohesive slab above it. Further north, this surface hoar layer is 60-120 cm down and has been sporadically reactive to skiers, most recently on north-west facing alpine slopes near Golden. At alpine elevations, this interface exists as a surface hoar/facet layer sitting on a crust. The lower snowpack is generally considered to be well settled. Solar aspects may now have sun crust from the recent warm temperatures. New and old wind slabs may be found in the lee of ridges and ribs on a variety of slopes, and surface hoar is forming in protected cool areas.

Problems

Wind Slabs

Thin wind slabs may continue to develop due to forecast new snow and wind. Southeast winds may create some reverse loading in the alpine.

Be cautious as you transition into wind affected terrain. >Use ridges or ribs to avoid pockets of wind loaded snow. >

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Buried weak layers of surface hoar may be triggered by human activity. This problem is more likely in the area west of Kimberley, but may be found in shallow snowpack areas across the region.

Dig down to find and test weak layers before committing to a big line. >Avoid exposed alpine faces, especially in the north of the region.>Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved, especially in the south of the region.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Jan 5th, 2016 2:00PM