Conditions Report: Alyeska

Alaska, known for it's deep, maritime snowpack, is in the midst of a deep slab avalanche xyxle more commonly associated with Continental areas like Colorado. South-central Alaska suffered from a very dry October, November, and early December. A total of 80 inches of snow fell during early winter. These advanced facets were then quickly loaded with 190 inches of snow in late December/early January. Needless to say, things got sketchy fast--and they will be for some time to come. This Wednesday, a skier triggered a deep, large avalanche on Tincan, a popular run on Turnagain.


John Fitzgerald recently wrote a synopsis of this skier triggered avalanche on Tincan--a run often skied by those looking for somewhere "safe." It averaged 8-10' deep and ran nearly a 1/4 mile wide.

His report can be found here:
http://www.cnfaic.org/observations/fotogallery.php?id=p2350&year=&map=&month=

Deep slab instabilities are extremely unpredictable. Deep slabs also have the ability to break unpredictably higher than soft slabs which usually break at steep, convex rollovers--therefore, traditional start-zones and safe-zones do not necessarily apply. These avalanches tend to defy historical patterns, a complication that contributed to the death this year of a seasoned Alpine Meadows Ski Patrolman, Bill Foster. It was also a deep slab instability, due to similar weather conditions, that killed Jackson Hole Ski Patroller Mark "Big Wally" Wolling in January of 2010.

If you are skiing in Alaska right now, please read this post by Andy Dietrick from the Alyeska Ski Patrol:

http://www.cnfaic.org/observations/fotogallery.php?id=p2349&remap=&year=2013&month=last30

The Alyeska Ski Patrol has posted a You Tube video showing the dramatic results at the ski area during avalanche hazard mitigation.

Adding to their complexity, deep slabs have the ability to lie dormant for long periods of time before being re-activated by rapid warming or heavy loading. As Fitzgerlad points out in his report:

Unfortunately, this problem will likely linger for a long time, with alternating periods of dormancy and reactivation. Other events like this are possible for the foreseeable future.

The best solution as a skier or rider is patience, which powder hounds are not famous for. Nonetheless, maritime areas like Alaska do usually heal with time. In my 10 years working for Valdez Heli-Ski Guides I have never seen a deep slab instability persist into March. I will certainly be hoping, for the sake of Alaskan locals, that is heals long before that, but it will be interesting to see.