Avalanche Advisory

Turnagain Area Avalanche Advisory
Friday, March 21st 2014 7:00 am by Graham Predeger
ARCHIVED ADVISORY - All advisories expire after 24 hours from the posting date/time.
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The Bottom Line

A MODERATE avalanche danger continues to persist above treeline where weak snow exists above and below a series of crusts.  The probability of triggering a large avalanche today is low but the consequences remain high making safe travel protocol in the mountains right now absolutely critical.

Below treeline and on slopes under 35 degrees the avalanche danger is LOW today.

Please take a look at the Observations page for several write-ups CNFAIC staff has been able to compile of some of last weekends large, human-triggered avalanches.

 Show the Complete North American Avalanche Danger Scale
2 Moderate Alpine / Above 2,500' Travel Advice: Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
1 Low Treeline / 1,000'-2,500' Travel Advice: Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
1 Low Below Treeline / Below 1,000' Travel Advice: Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Special Announcement

Come join CNFAIC forecasters this Sunday for a FREE AVALANCHE RESCUE WORKSHOP at Turnagain Pass!  Focus will be on beacon practice through avalanche rescue scenarios.  We’ll meet in the motorized lot at 10:30am and wrap up by 1:30pm.  Skiers and sledders welcome!  Please drop a note to to reserve a spot for you and your crew, as space is limited.

Avalanche Problem 1

Almost a full week has passed now since any reports of major avalanche activity in the backcountry, and with people pushing into bigger terrain without incident yesterday this points toward a stabilizing snowpack. 

We do know however that weak snow still exists below the March 10-14th storm cycle that produced a slab up to 5’ deep.  It is becoming increasingly more difficult to upset this weak layer but if affected the resulting avalanche will be large and potentially un-survivable.  Tracks on a slope do not correlate to stability when dealing with a deep slab avalanche problem.  Shallow spots in a slab are likely areas to trigger an avalanche up to 5’ in depth today.  These may be difficult to recognize but some clues to a shallow, tapering slab include areas near rock or tree outcroppings or directly adjacent to wind-stripped terrain.

                            This photo from the Crested Butte Avalanche Center is a good illustration of how a slab tapers.  
                            Likely trigger spot for this avalanche would be near the lower right corner of the photo where the
                            slab is thin and a human is more likely to affect the weak layer.

If your tolerance for risk is taking you into bigger, steeper terrain today it is fundamental that you and your group exercise safe backcountry travel protocol.  This includes communicating travel plans, escape routes and islands of safety.  Expose only one person at a time on a slope and re-group in safe areas well away from run-out zones.

Avalanche Problem 2

Strong solar radiation late in the day continues to push cornices toward their natural breaking point.  Add a skier or snowmachiner on a ridge in close proximity to one of these backcountry bombs and cornice failure will be possible.   Your best bet to mitigate this problem today and everyday is to give cornices a very wide berth when travelling on ridges and limit your exposure when travelling beneath. 

Mountain Weather

The first day of Spring yesterday did not disappoint with sunny skies, temperatures reaching into the mid-30's at 1,000' and light to moderate winds out of the east.  

Today we can expect partly cloudy skies by this afternoon, winds out of the east in the 10-25mph range and temperatures again warming into the mid to high 30's by the heat of the day.  Looking into the weekend an upper level ridge will persist over the mainland, keeping southcentral Alaska mostly sunny and completely dry at least through early 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: May 06, 2019 )

Glacier District
Johnson Pass: ClosedClosed as of 4.3.19
Placer River: ClosedClosed as of 3.20.19 due to lack of snow.
Skookum Drainage: ClosedPlacer access closed as of 3.20.19 due to lack of snow.
Turnagain Pass: ClosedClosed as of 5/6. Thanks for a great season all, see you next winter!
Twentymile: ClosedClosed as of 3.20.19 due to lack of snow.
Seward District
Carter Lake: Closed
Lost Lake Trail: ClosedClosed as of 3.22.19 due to lack of snow
Primrose Trail: ClosedClosed as of 4.3.19 due to lack of snow
Resurrection Pass Trail: ClosedClosed for the 2018/19 season. Next season will be open to motorized use.
Snug Harbor: ClosedClose as of 5.1.2019
South Fork Snow River Corridor: ClosedClosed as of 3.20.19 due to lack of snow.
Summit Lake: Closed

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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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