CNFAIC LogoCNFAIC Logo

Avalanche Advisory

Turnagain Area Avalanche Advisory
Forecaster:   John Fitzgerald  
Saturday, February 15th 2014
Created: Feb 15th 6:41 am
3 Considerable Alpine / Above 2,500' Travel Advice: Dangerous avalanche conditions. Careful snowpack evaluation, cautious routefinding and conservative decision-making essential.
2 Moderate Treeline / 1,000'-2,500' Travel Advice: Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
2 Moderate Below Treeline / Below 1,000' Travel Advice: Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
 Show the Complete North American Avalanche Danger Scale
Deuter USA
Special Announcement

New snow over the past week is helping to rebuild the snowpack in areas that were showing bare ground after the January rain and warmth.  Motorized areas on the Chugach National Forest remain closed to avoid resource damage.  The good news is that we are getting closer to re opening these areas.  Check the bottom of the page for the latest updates as well as the Chugach National Forest website.

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------

There are still a few raffle tickets left for the February 21st drawing to win some great prizes including a day of Valdez Heli Skiing or Alaska Airlines Tickets!  Join the Friends of CNFAIC at The Midnight Sun Brewery from 6-8PM Sunday night to pick up your raffle ticket and some free swag!


The Bottom Line

The avalanche hazard is CONSIDERABLE today for all terrain above treeline.  Dangerous conditions exist.  Wind slabs up to 2 feet in depth as well as loose snow avalanches are likely to be triggered by humans venturing above treeline.  Natural avalanches are also possible in the higher elevations today.

Below treeline the hazard is MODERATE, where it will be possible for humans to trigger loose snow and soft slab avalanches up to 18" in depth on all aspects.  

Knowledge of terrain above will also be critical today, as avalanches in the higher elevations have the potential to run into lower elevation areas.


Primary Concern

Snowfall amounts over the past 24 hours ranging from 6” in the lower elevations to 18” in the higher elevations are bringing with it all of the issues related to storm snow.

Loose Snow avalanches
Yesterday my partner and I were able to easily produce sluffing in steep terrain, generally over 40 degrees.  Loose snow sluffs will be easy to trigger today and could entrain enough snow to knock people off of their feet.  This issue becomes exacerbated when traveling above terrain traps such as cliffs, trees, and gullies.

Storm Slabs
Enough snow has fallen over the past 24 hours to create slabs without the presence of wind.  While the general set up on the surface is loose snow, slabs were beginning to form in sheltered areas late in the day yesterday.  Be on the lookout for shooting cracks when traveling on terrain 35 degrees and above today.  While these slabs are generally soft, the potential exists for them to propagate across slopes and run far.

Wind slabs
Winds out of the East cranked up enough yesterday afternoon and into the night to create wind slabs up to 2 feet in depth that will be very sensitive to the weight of a person today.  Avoiding leeward slopes above 35 degrees is your best bet for avoiding this problem.  These newly formed slabs also have the potential to trigger deeper layers in the snowpack.


Secondary Concern

The most prominent weak layer above 3,500’ is facets sitting on the stout January crust.  This layer (along with the crust) has been associated with remotely triggered avalanches over the last week.  Since Feb 7th, up to 30” of snow with 2” of water has fallen in the higher elevations.  This slab has had time to settle and become more dense.  The interface between this slab and the January crust is suspect.  Visibility yesterday limited our ability to assess this interface.  Because of this lack of information, this layer & the slab above it are guilty until proven innocent.  Avoidance of steep (over 35 degree) upper elevation starting zones and cross loaded gullies will be the best management tactic related to this problem today.


Mountain Weather

Winter Part 2 has arrived!

In the past 24 hours the Turnagain Pass SNOTEL site has picked up 14” of new snow with 1” of water.  The Girdwood Valley has seen less amounts, with stations averaging 6-8” snow with .5” of water.  Winds that picked up overnight have calmed this morning.  Sunburst averaged 20mph with gust to 69mph.  Ridge top temps have averaged in the low teens and are currently reading in the high single digits F.

Today expect a continuation of light snowfall.  Accumulations of 2-4” are possible.  Temperatures at 1,000’ will be in the teens to low 20s F.  Winds will be out of the East at 10-15 mph.

A very large area of Low pressure centered over Kodiak island will remain in place through the weekend.  Expect light snow with occasional breaks in the clouds to continue through the next several days.

This is a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area (this advisory does not apply to highways, railroads, or operating ski areas).

Winter snowmachine use open/closed status and riding conditions updates

Riding status is not associated with avalanche danger. An area will be open to motorized use in accordance to the Forest Management Plan when snow coverage is adequate to protect underlying vegetation. Backcountry hazards including avalanche hazard are always present regardless of the open status of motorized use areas.

(Updated: Nov 18, 2017 )

AREA STATUS WEATHER AND RIDING CONDITIONS
Glacier District
Johnson Pass: Closed
Placer River: Closed
Skookum Drainage: Closed
Turnagain Pass: ClosedOnly a few inches of snow sits at the motorized lot, not enough to open for snowmachining at this time. Updated Nov. 18, 2017
Twentymile: Closed
Seward District
Carter Lake: Closed
Lost Lake Trail: Closed
Primrose Trail: Closed
Resurrection Pass Trail: ClosedResurrection Pass trail is expected to open to snowmachine use during the 2017/18 winter season.
Snug Harbor: Closed
South Fork Snow River Corridor: Closed
Summit Lake: Closed

Subscribe to the Turnagain Area Avalanche Advisory:

The information in this advisory is from the U.S. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur. This advisory provided by the Chugach National Forest, in partnership with Friends of the Chugach National Forest Avalanche Information Center.


USFS SNOW AND AVALANCHE HOTLINE (907) 754-2369
If you have comments or questions regarding CNFAIC operations or winter recreation management, please email staff@chugachavalanche.org
© 2017 Chugach National Forest Avalanche Information Center. All rights reserved.
FCNFAIC