It's been a week since last Friday's storm event which produced dozens of deep, hard slab avalanches failing on a persistent weak layer of of sugary, faceted snow at the base of the snow pack. The heavy load provided a significant test for slopes that didn't avalanche, and time and warmer temperatures have aided in the healing process. Stability tests performed by myself and local observers this week indicate that an avalanche of this size would be harder to trigger now but if you did find the right spot, the result would be devastating. Likely trigger points include shallow, rocky areas, lines along slope margins, or steep convexities. With avalanches of this magnitude remaining a real possibility, careful terrain choices remain imperative and in the final analysis, venturing on to steep, north facing terrain is still a little bit like walking through a mine field.

Photo illustrates strong slab over weak, October facets. Extended column tests produced no results and it's becoming harder for the weight of a skier or rider to affect this basal weak layer. Propagation saw tests however show that it is still possible for a slab to fail and propagate. Shallower snowpack areas are likely trigger points.

You may still be able to find some isolated slabs of wind drifted snow out there in the high country. Potentially unstable drifts are most likely to be found on northerly aspects but they may also exist on slopes with a west or southeasterly tilt. In some cases they may be found adjacent to bare slopes where a subtle terrain feature such as a sub-ridge or gully wall has caused deposition on the leeward side. Wind slabs are recognizable by their smooth, rounded appearance, or hollow sound and feel. Cracking is a sign of instability. On northerly aspects, wind drifted snow has added stress to older slabs on top of a buried persistent weak layer and dangerous, human triggered avalanches 3'-5' deep are possible. Continue to avoid steep, wind drifted slopes.

Areas of a wind drifted snow on a northerly aspect from south and westerly winds. Note the rippled effect indicating recent drifting as well as overhanging cornices indicating wind direction and loading areas on leeward aspects. Chris Benson photo.