CNFAIC LogoCNFAIC Logo

Avalanche Advisory

Turnagain Area Avalanche Advisory
Forecaster:   Wendy Wagner  
Wednesday, December 14th 2016
Created: Dec 14th 5:57 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
Alaska Alpine Adventures LLC
Special Announcement

Tomorrow night: Fireside Chat: Avalanche Awareness and Rescue with the CNFAIC in Girdwood at the Powder Hound Ski Shop! December 15 @ 6:30 pm - 8:00 pm. FREE!


The Bottom Line

A LOW avalanche danger remains in the mountains surrounding Turnagain Pass. Popping out an old wind slab sitting on faceted snow, breaking off a chunk of cornice or triggering a larger slab avalanche are all in the realm of 'unlikely possibilities'. Most suspect terrain will be steep slopes further away from the road corridor and periphery zones like the Girdwood Valley and Placer Valley. 

*Good travel habits should not be left at home during 'green light' conditions; expose one person at a time, watch your partners, have an escape route planned and group up in safe zones. 


Primary Concern

While we patiently wait for the next snow event, folks continue to get out and enjoy the blue sky days and what snow we do have. To generalize, the snowpack above treeline is anywhere from 3-6' thick on the North end of Turnagain Pass and 2-3' thick on the South end the Pass (more snow typically falls on the North end because it's closer to the Arm). Along the road the snowpack is anywhere form 6" to 20". It has been 14 days since our last snow event that added 6-10+". The snowpack is generally stable and turning to sugar snow from the top down (near surface faceting) and in many thinner areas like Summit Lake, from the bottom up (forming depth hoar). Essentially, these cold days are creating a very weak foundation for the next load of snow. 

If you are headed out today, watch for wind slabs near ridgelines that are sitting on weak faceted snow (we received a report describing a wind slab that collapsed but didn't release yesterday in the Girdwood Valley). Additionally, watch for cornices and 'facet' sluffs on very steep terrain. Last, the 'outlier' slab avalanche that could fail mid-pack due to the Nov 16 buried surface hoar is worth keeping in the back of your head. 


Mountain Weather

It looks as though yesterday closed up the last of the single digit temperatures and bluebird skies. A large area of low pressure is pushing in and scouring out the cold air. Temperatures warmed up to the 15-25F range from valley bottoms to ridgetops overnight and ridgetop winds have remained light from a Westerly direction. 

For today we should see mostly clear skies with some valley fog. Temperatures will remain in the 15-20F range in the parking lots and mid 20'sF along the ridgelines. Winds are expected to be Northwesterly around 5-10mph on the ridgelines.

Again, the more interesting news is this weekend and next week. If the stars align we should see snow accumulation as early as Thursday, and not only snow to sea level, but snow falling at Hatcher Pass. At his point, models are showing a Southwest flow direction for Thursday into Friday - favoring Hatcher Pass as well as Anchorage. The larger system for Sunday looks to favor Turnagain Pass.

Check out part of the National Weather Service's long term discussion below:

".LONG TERM FORECAST (Days 3 through 7...Fri through Tue)...

A pattern change remains on track for late this week into next
week .... will help to usher a train of fast-moving systems ... This
will bring a moderating trend to temperatures......... as well as
increased precipitation chances, especially along the coastlines.
Trends suggest there may be ample snow opportunities inland
by early next week as well."

 

 

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

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880') 18  20 
Summit Lake (1400') 16 
Alyeska Mid (1700') 20 

 

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

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812') 18  15 
Seattle Ridge(2400') 20   SW 14 

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 16, 2017 )

AREA STATUS WEATHER AND RIDING CONDITIONS
Glacier District
Johnson Pass: Closed
Placer River: Closed
Skookum Drainage: Closed
Turnagain Pass: ClosedThanks all for a safe and fun season on the Chugach NF! Stay tuned for the 2017/18 season. #playsafe #snowtosealevel
Twentymile: Closed
Seward District
Carter Lake: Closed
Lost Lake Trail: Closed
Primrose Trail: Closed
Resurrection Pass Trail: ClosedResurrection Pass trail will be open to snowmachine use during the 2017/18 winter season.
Snug Harbor: Closed
South Fork Snow River Corridor: Closed
Summit Lake: Closed

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