Avalanche Forecast

Issued: Dec 13th, 2014 8:15AM

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

rbuhler, Avalanche Canada

South Columbia.

Stability is improving but there are still avalanche problems out there. If you see anything interesting, please submit an observation using our new website tool. For more details see: http://goo.gl/Tj0xPC

Summary

Confidence

Fair - Due to the number of field observations

Weather Forecast

A ridge of high pressure will persist for several days. On Sunday, expect mostly sunny conditions, treeline temperatures around -4C, and light winds in the alpine. Monday and Tuesday will be much the same with mostly sunny conditions, treeline temperatures around -8C, and light winds in the alpine.

Avalanche Summary

Initial reports from Saturday suggest that avalanche activity has tapered off since the storm ended and temperatures dropped. On Friday there was isolated activity including a natural size 2.5 wind slab and some explosive triggered storm slabs to size 1.5. Widespread natural avalanche activity up to size 3 was reported on Wednesday and Thursday.

Snowpack Summary

The rain soaked snow surface has now refrozen with colder temperatures. A thick supportive crust is expected to around treeline and a breakable crust is expected in the lower part of the alpine. The highest elevations of the alpine may still have dry snow on the surface but this has likely been heavily wind-affected by recent strong southerly winds. A thick rain crust with facets from early November is buried over 1 m down. Snowpack tests on this deep weak layers are showing improving results, but in some locations these layers are still reactive and have the potential to release large slab avalanches.

Problems

Wind Slabs

Use caution in the high alpine where most of the recent precipitation has fallen as snow. Watch for wind loaded or cross loaded slopes well below ridge crests from the past week of strong southerly winds.

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

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Persistent Slabs

The likelihood of triggering a persistent slab should be decreasing with dropping temperatures but be wary of any slope that did not release during the storms or has been reloaded.

Avoid common trigger zones including thin snowpack areas, near rocky outcrops, and steep alpine slopes.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Valid until: Dec 14th, 2014 2:00PM