Turnagain Pass

Due to early season conditions, for both the snowpack and our operations, we will be issuing intermittent snow and avalanche updates until November 17th, as conditions dictate.

BOTTOM LINE
Currently human triggered avalanche conditions are present in our mountains. Despite the overall snow cover being a mere 1-2′ deep, slab avalanches have released near and above treeline on all aspects since Saturday Nov. 2nd. These conditions are forecast to persist and become more significant with the next storm (see below for more detailed information).

This is shaping up to be a season where the phrase “if it’s steep enough to ride, it’s steep enough to slide” rings true… Terrain management will be the key for safe backcountry recreation. If you have not done so already, replace those beacon batteries, dust off your rescue gear (is it still in good shape?) and run through some drills to become reacquainted with it all.  

ANNOUNCEMENTS
Keep checking our photos/observations page for early season information.

Also, check out the calendar page for free awareness classes and other avalanche education courses offered in our area. The first of four free “fireside chats” starts Nov. 8th in Girdwood (see calendar for details).

SNOWPACK and AVALANCHE DISCUSSION
The start to the 2012/13 season is significantly different from last season when we had a generally stable snowpack. To date, we are dealing with a slab avalanche problem consisting of a layer of very weak snow, 3-10″ thick, with a layer of strong snow, 4-18″, on top. The set up began when around a foot of snow fell in mid October and sat under clear skies for two weeks becoming quite faceted with surface hoar growing on top. On November 2nd, 6-10″ of medium density snow fell with moderate (10-25mph) winds above treeline and formed very sensitive storm and wind slabs. Slab thickness varied from 4-18″ in depth. Both natural and human triggered avalanches released just after the storm while human triggered avalanches continued for several days following the snowfall and continue to be possible to trigger this week. The weak layer was, and is, the faceted snow. The photos below paint the picture as to how touchy this early season snowpack is right now:

The above avalanche was skier triggered on the west shoulder of Tincan just above treeline. Crown depth was reported at 6″-2′ deep and propagated up to 300 yards! (full extent of propagation cannot be seen in the photo)

Above avalanche is looking down from Sunburst’s west shoulder (~3200ft elev.). This took out a section of snow where the up track is commonly set. Crown 6-12″ deep x 50′-70′ wide, ran over 1000′ off to the north side of the ridge into unforgiving terrain. Just because it is a ridge doesn’t mean it cannot slide.

Future concerns:
With the next storm, possibly this weekend, natural and human triggered avalanches will likely ramp up another notch. Slabs will be thicker and propagation could be wider. Remote triggers (for example, triggering an avalanche on top of you from below) will be possible. Very conservative route finding will be the ticket to getting back to the parking lot safely. This includes keeping slope angles under 30 degrees, including slopes above you. All aspects are suspect and even low elevations with slopes looming above are a concern. Any cracking and collapsing (whoomphing) are obvious clues the snow is unstable and if steep enough will most likely slide.

Cracking on the sunburst ridge.

Ice climbers:
Take a look at this observation and forecaster note HERE.