CNFAIC LogoCNFAIC Logo

Avalanche Advisory

Turnagain Area Avalanche Advisory
Thursday, November 29th 2018 7:00 am by Heather Thamm
ARCHIVED ADVISORY - All advisories expire after 24 hours from the posting date/time.
Previous ForecastNext Forecast
BROUGHT TO YOU BY
The Bottom Line

The avalanche danger is MODERATE in the Alpine where triggering a slab avalanche is possible on all aspects. Below 2500' the danger is LOW where freezing temperature are helping a thin and wet snowpack form a crust. 


 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.
0 NO RATING Below Treeline / Below 1,000'
Special Announcement

The Friends of the CNFAIC have two scholarships dedicated to avalanche education. The funds generated to make these possible are in celebration of Rob Hammel and Amy Downing, their love and passion for the mountains, and to help others stay safe. We encourage you to read each one and apply if you fit the need, or pass along to someone who could benefit. Applications due on Dec 1st.

Rob Hammel Scholarship Fund – For recreational users and professional avalanche workers.

Amy Downing Scholarship Fund – For recreational users.


Avalanche Problem 1

Storm Slabs

Almost Certain
Very Likely
Likely
Possible
Unlikely

Chance

Historic
Very Large
Large
Small

Size

Last night was the first freeze in five days since a series of warm and wet storms ended yesterday morning.  Not much snow exists below 2000' due to heavy rain that may have reached ridgetops at times. We don't have a lot of information from the upper elevations, above 2500’, at this point. We know 4+’ of snow fell over a four-day period and strong Easterly winds have loaded leeward features and cross-loaded other aspects. Prior to this storm a melt-freeze crust and surface hoar formed in the upper elevations. We don’t know how much avalanche activity occurred during the storm and if this poor structure is lingering in places that haven’t avalanched.

Today triggering an avalanche is possible in the Alpine and could be large enough to bury a person. If you hike into the Alpine where there is enough snow to slide ease into avalanche terrain with a cautious mindset. We are still in the 48-hour period since heavy snow and strong winds formed storm slabs. Avoid avalanche terrain if you observe any signs of instability: recent avalanches, shooting cracks, or whumpfing

Webcam pictures from DOT weather station provided our first glimpse into the Alpine yesterday afternoon - Northern and Western aspects of Tincan above 2000'. 

 

 

Brief clearing in the afternoon provided a nice glimpse of an Eastern aspect of Seattle Ridge. Note how little snow exists in the lower elevations.

 

 

West aspect of Butch in foreground and Northern aspects of Tenderfoot and Tri-Tip in the background. Photo from Mon Nov. 26  at Lower Summit Lake.


Mountain Weather

Yesterday: Moderate Easterly ridgetop winds diminished yesterday morning becoming light by early evening. Skies were obscure most of the day a broken period late afternoon. Temperatures dropped below freezing last night allowing 0.1” of snow water equivalent to fall as an inch of snow to sea level from Girdwood to Turnagain Pass last night.

Today: Scattered snow showers and a trace of snow are possible this morning with clearing skies in the forecast this afternoon. In the upper elevations temps will average in the low 20Fs and upper 20Fs near sea level.  Winds will remain light and variable.

Tomorrow: Temperatures will start to increase as another storm moves into our region Friday into Saturday. This storm will have a Southwesterly flow, which typically favors Hatcher Pass for precipitation. Temperatures are expected to reach above freezing and rain is likely in the mid and lower elevations. Increasing temps and winds are expected in the Western Chugach and Kenai Mountain.

 *Seattle Ridge weather station stopped collecting wind data at 10 pm on Nov 27, 2018. 

PRECIPITATION 24-hour data (6am - 6am)

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880') 29   1" 0.1  10 
Summit Lake (1400') 27 
Alyeska Mid (1700') 30  1" 0.16  *N/A 

 

RIDGETOP 24-hour data (6am - 6am)

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812') 21  ENE  27 
Seattle Ridge(2400') 26  *N/A  *N/A   *N/A  

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 22, 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: ClosedClosed as of 3/22. Unfortunately HEAVY rain over the past week has washed much of the snow off the lower stretches of this trail.
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
© 2019 Chugach National Forest Avalanche Information Center. All rights reserved.
FCNFAIC