CNFAIC LogoCNFAIC Logo

Avalanche Advisory

Turnagain Area Avalanche Advisory
Forecaster:   Wendy Wagner  
Wednesday, December 11th 2013
Created: Dec 10th 6:50 am
1 Low Alpine / Above 2,500' Travel Advice: Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
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.
 Show the Complete North American Avalanche Danger Scale
Deuter USA
The Bottom Line

We continue to have an overall LOW avalanche danger in the mountains surrounding Turnagain Pass. Avalanche activity is unlikely. The main concerns for backcountry travelers are conditions associated with an early season and thin snow cover.

This advisory will extend through tomorrow, Wednesday. The next advisory will be Thursday morning, December 12th.


Primary Concern

The recent cold temperatures, after the early December warm spell, have essentially tied the surface of our snowpack together with a crust. The crust is unsupportable in most areas and breaking through into the weak sugar snow below can make skiing and riding challenging. You can see a few recent observations discussing this HERE and HERE.

Again, the main hazards in the backcountry are rocks and other objects near the snow surface. I would also argue that an additional hazard is negotiating the ‘ankle grabbing’ surface crust. 

Snowpack Discussion:
A layer of surface hoar has formed on the top of our snowpack during the past few days. This is anchored to the crust that caps the snowpack and forms a surface hoar/crust combination. Though the combo not dangerous now, it will have our attention when we get our next shot of snow and a slab forms on top. 

           
Surface hoar on Seattle Ridge (2,500'). Photo: Fitz                  Surface hoar on breakable crust near Ingram Creek. Photo: Bob Sutherland


Mountain Weather

During the past 24-hours we have been on the north side of a large low pressure system sitting well to our south. This has brought cloud cover but no precipitation to our zone. Temperatures have been in the 20’s F at most locations and wind light from the southeast.

This pattern will remain through the day before it breaks down and colder air ushers in from the north tomorrow. We can expect partly cloudy skies today with temperatures remaining in the mid to upper 20’s F across the board. We do have a chance for a few flurries. Winds will be light and variable before turning northeast tonight with the approach of the colder polar air. Wednesday we should see skies clear and temperatures in the teens and single digits with light northerly winds.

If you have read this far in the advisory you may be happy to hear that a shift in our weather pattern is coming this weekend. Confidence looks to be high at the NWS that a decent precipitation event is headed our way. Let’s cross our fingers the models are right. See their full discussion HERE.

 

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: Apr 11, 2017 )

AREA STATUS WEATHER AND RIDING CONDITIONS
Glacier District
Johnson Pass: OpenPlease park on road in and leave the turnaround (near outhouse) open for trailers to turn around.
Placer River: OpenWide swaths of open river in the Placer Valley. Travel with extreme caution!
Skookum Drainage: ClosedSKOOKUM DRAINAGE CLOSED TO MOTORIZED USE ON APRIL 1 annually as per the Chugach National Forest Plan document.
Turnagain Pass: Open
Twentymile: ClosedClosed for the remainder of the 2017 season.
Seward District
Carter Lake: Open
Lost Lake Trail: OpenPlease STAY ON existing and hardened trail surface through the lower sections of this route.
Primrose Trail: OpenPlease STAY ON existing and hardened trail surface through the lower sections of this route.
Resurrection Pass Trail: ClosedClosed for 2016/17 winter season. This is a non-motorized season. This alternates every other year and will open again during the 2017/18 winter.
Snug Harbor: Open
South Fork Snow River Corridor: Open
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
© 2017 Chugach National Forest Avalanche Information Center. All rights reserved.
FCNFAIC