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Turnagain Area Avalanche Advisory
Friday, March 12th 2010 6:01 am by CNFAIC Staff
ARCHIVED ADVISORY - All advisories expire after 24 hours from the posting date/time.
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BROUGHT TO YOU BY
The Bottom Line
Good morning backcountry travelers this is Carl Skustad with the Chugach National Forest Avalanche Information Center on Friday March 12th, 2010 at 7 am. This will serve as 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).


WEATHER ROUNDUP
Southeast winds remain light this morning. Temps are chilly ranging from -9 at Summit Lake to 8 at sealevel in Girdwood. Ridgetops are seeing 2 to -3 degrees F. The radar image shows scattered precip over Prince William Sound and the satellite indicated partly clear. No new snow in the last 24 hours.


AVALANCHE DISCUSSION
Todays danger level will stay at MODERATE due to lack of significant weather in the past 24-48 hours, time since the last major storm, and no significant weather forecasted for today.


Moderate avalanche danger means heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern. Natural avalanches unlikely; human triggered avalanches possible.


365-yes_2010_Mar_11_1938-3.jpg


We received a report of a human triggered avalanche on the south aspect of Cornbiscuit yesterday afternoon. The slope had been skied 5 plus times prior to release. The avalanche was triggered when a pair of skinners pushed the skin track farther up the ridge than previous. The avalanche was triggered in a shallower snowpack near some rocks and propagated 300-500 ft across. It broke 1-3 ft deep and ran full track to the valley below. No one was caught. The group had dug a previous pit and found fair to good stability. This proves the snowpacks spacial variability. The weak layer is unclear. No CNFAIC Staff reports of any signs of instability in the area.


364-yes_2010_Mar_11_1938-1.jpg


Areas of concern today include hanging snow fields in complex terrain. Old wind slabs may be present. Weak layers may be closer to the surface and able to be triggered where the snowpack is shallower. Take time to test the snow you are traveling on. Keep the human factors in check today. Stability may be moderate, but this kind of snow, weather and stability can still produce dangerous avalanches.

Snowfall totals from Mondays storm at the highway elevation snow stakes at Turnagain Pass were 31 inches at Eddies, 31 inches at the Motorized lot, 22 inches at Sunburst, and 19 inches at Johnson Pass.

Glide cracks are secondary concern today since this new load of snow is still actively settling and moving. A full depth release avalanched a couple days before Mondays storm in Girdwood Valley (see photo gallery). Glide cracks are like cornices in that they are wild cards that are very difficult to predict.


WEATHER FORECAST (National Weather Service)
WESTERN PRINCE WILLIAM SOUND-
INCLUDING...WHITTIER...SEWARD...GIRDWOOD...MOOSE PASS
500 AM AKST FRI MAR 12 2010

.TODAY...MOSTLY CLOUDY WITH SCATTERED SNOW SHOWERS. HIGHS 15 TO
25. VARIABLE WIND TO 10 MPH. NEAR WHITTIER...WEST WIND 10 TO 20 MPH.
.TONIGHT...MOSTLY CLOUDY WITH SCATTERED SNOW SHOWERS. LOWS 10 TO
20 ABOVE. VARIABLE WIND TO 10 MPH.
.SATURDAY...SNOW LIKELY. SNOW ACCUMULATION UP TO 2 INCHES. HIGHS
AROUND 30. VARIABLE WIND 10 MPH EXCEPT NORTH 15 TO 25 MPH NEAR
SEWARD.
.SATURDAY NIGHT...SNOW LIKELY. LOWS IN THE 20S. NORTH WIND 10 TO
15 MPH EXCEPT NORTH 20 TO 30 MPH NEAR SEWARD.
.SUNDAY...SNOW LIKELY. HIGHS IN THE 30S. NORTHEAST WIND 10 TO
15 MPH EXCEPT NORTH 15 TO 25 MPH NEAR SEWARD.
.SUNDAY NIGHT...SNOW LIKELY. LOWS IN THE UPPER 20S TO LOWER 30S..

TEMPERATURE / PRECIPITATION

SEWARD 19 14 31 / 40 40 70
GIRDWOOD 26 14 29 / 30 30 40


WEATHER STATION SUMMARY for last 24 hours at TURNAGAIN PASS
3800-Sunburst Wx Station
Current Temp: -3 (3 degrees warmer than yesterday)
Winds: sensor not working this morning

2600-Seattle Ridge Wx Station
Winds: sensor not working this morning

1800-Center Ridge Wx Station
Current Temp: 0
Precip: 0, total snowpack 131 after anCNFAIC Staff 2 inches of settlement.

Thanks for checking todays avalanche advisory. The next one will be posted tomorrow Saturday March 13, 2010.

 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.
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.

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: Mar 20, 2019 )

AREA STATUS WEATHER AND RIDING CONDITIONS
Glacier District
Johnson Pass: Open
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: Open
Twentymile: ClosedClosed as of 3.20.19 due to lack of snow.
Seward District
Carter Lake: Open
Lost Lake Trail: OpenPlease stay on trail to avoid resource damage through forested areas.
Primrose Trail: OpenPlease stay on trail to avoid resource damage through forested areas.
Resurrection Pass Trail: ClosedClosed for the 2018/19 season. Next season will be open to motorized use.
Snug Harbor: Open
South Fork Snow River Corridor: ClosedClosed as of 3.20.19 due to lack of snow.
Summit Lake: Open

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
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