Avalanche Advisory

Turnagain Area Avalanche Advisory
Thursday, January 3rd 2013 6:48 am by John Fitzgerald
ARCHIVED ADVISORY - All advisories expire after 24 hours from the posting date/time.
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The Bottom Line

The danger will rise to HIGH above treeline today, where newly formed wind slabs will become very sensitive to human triggers.  Below treeline the hazard remains at CONSIDERABLE, where human triggered avalanches are still likely and natural avalanches are possible.

 Show the Complete North American Avalanche Danger Scale
4 High Alpine / Above 2,500' Travel Advice: Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.
3 Considerable Treeline / 1,000'-2,500' Travel Advice: Dangerous avalanche conditions. Careful snowpack evaluation, cautious routefinding and conservative decision-making essential.
3 Considerable Below Treeline / Below 1,000' Travel Advice: Dangerous avalanche conditions. Careful snowpack evaluation, cautious routefinding and conservative decision-making essential.
Special Announcement

World champion big mountain steep skier Dean Cummings will be at the Sitzmark Bar and Grill at 7 pm tonight, Thursday January 3rd.  Dean will be sharing his Steep Life Protocols for smart travel in avalanche-prone backcountry terrain. Afterward, Dean will be available for poster signings in an informal meet and greet atmosphere. Be sure to join us for a night of big mountain skiing at its finest!

Avalanche Problem 1

Yesterday a skier on Tincan triggered a large avalanche and fortunately avoided burial.  This was a very destructive avalanche, pulling out most of the snowpack on this slope.  For info and photos of this avalanche click here, here and here.  Stay tuned for more info on this avalanche.

During times of intense precip, like today, the likelihood of triggering deep slabs goes up.  As storms subside the likelihood will go down.  The high consequences, however, do not change.

The fact remains, and will remain for a long time, that weak layers near the ground are still weak.  All it takes is finding a spot where the slab is less deep, i.e. where we can impact the layer more easily, and large destructive avalanches will occur.  These trigger points are often very difficult to detect.  The usual warning signs of recent avalanches, shooting cracks or whoompfing may not present themselves before it's too late.  

Observations from New Years Eve allowed us to see areas above treeline that have been greatly affected by high winds.  Some areas have been scoured to the ground while other areas are holding massive slabs.  With such a great variety of slab depths at the upper elevations, the potential to find a trigger point is now greater.  The best way to manage this problem today is to avoid terrain that is steep enough to slide.

Avalanche Problem 2

With up to 10 inches of new snow and 50 mph winds forecasted, expect wind deposited new snow to be sensitive to human triggers today.  The likelihood of getting wind slabs to release will be higher today than deep slabs.  However, the potential for relatively shallow avalanches to step down into deeper layers make this a problem not to be trifled with.  Below treeline and in sheltered areas, new storm snow unaffected by winds will also be a problem to look out for.

Mountain Weather

In the past 24 hours snowfall amounts have been in the 2-3" range, ridgetop winds have averaged 35 mph out of the East and temps have remained mild, with freezing levels hovering around the 1000' level.
Snowfall will pick up in intensity this morning and into the daytime hours, with total accumulations of up to 10" possible during the day.  Ridgetop winds will be 50-60 mph out of the SE, and temps at 1000' will be in the low 30s F.
The general pattern of unsettled weather will continue through the weekend.  Look for precip to continue and a gradual cooling trend to set up as we move into next week.

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: Feb 15, 2018 )

Glacier District
Johnson Pass: OpenPlease access trail thru open gate and park trucks/ trailers along the road toward the trailhead. Please keep the turnaround (near large signboard) clear for vehicles to TURN AROUND!
Placer River: OpenOpen 2/16. Please avoid private property and AKRR job site at Luebner Lake. Cross railroad tracks if needed, do not ride down tracks, it is illegal.
Skookum Drainage: OpenOpen 2/16. Please avoid private property and AKRR job site at Luebner Lake. Cross railroad tracks if needed, do not ride down tracks, it is illegal.
Turnagain Pass: OpenPlease avoid riding on “Rookie Hill“ and other areas with exposed vegetation. Thank you!
Twentymile: Closed
Seward District
Carter Lake: OpenOpen 2/16.
Lost Lake Trail: Closed
Primrose Trail: Closed
Resurrection Pass Trail: OpenResurrection Pass trail is open to snowmachine use during the 2017/18 winter season.
Snug Harbor: Open
South Fork Snow River Corridor: Closed
Summit Lake: Open

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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.

If you have comments or questions regarding CNFAIC operations or winter recreation management, please email
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