Avalanche Advisory

Turnagain Area Avalanche Advisory
Wednesday, January 10th 2018 4:34 am by Aleph Johnston-Bloom
ARCHIVED ADVISORY - All advisories expire after 24 hours from the posting date/time.
Previous ForecastNext Forecast
The Bottom Line

The avalanche danger is MODERATE on all slopes above 2,000' in elevation, where triggering a slab avalanche, breaking 1-3' deep on a weak layer of snow remains possible. Additionally, triggering a larger slab breaking near the ground remains possible at elevations above 3,000'. Watch out for loose snow avalanches in steep terrain. 

The danger is LOW near 2,000' and below. 

 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.
1 Low Below Treeline / Below 1,000' Travel Advice: Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Special Announcement
Our advisory page has changed! Information on the changes can be found HERE
*Coming up on January 13th there is a FREE avalanche rescue clinic at Hatcher Pass. Practice with your gear on your way to the backcountry - clinic runs from 11am - 1:30pm. 


Avalanche Problem 1

Persistent Slabs

Almost Certain
Very Likely


Very Large


As we move further from our last loading event (New Year's Storm) and cold temperatures degrade the upper layers of the snowpack, the chances of triggering a slab avalanche are decreasing. However, it is not something that should totally be ruled out yet. We know that the snow from the storm is sitting on either buried surface hoar, buried near-surface facets or in thin snowpack areas, facets near the ground. This means there is poor snowpack structure and a persistent slab set-up above 2000'. Snowpack tests over the past few days have shown variable results but point to the continued potential for triggering an avalanche.

For those riders and skiers headed out today:

  • Triggering a slab is most likely in the upper elevations above 2,000', where NO crusts exist in the top foot of the snowpack.
  • Several tracks may be on the slope before a slab releases and no signs saying 'the slope is unstable' are likely to be present.
  • Larger slopes, 35 degrees and steeper are more suspect and those with rocky features. 
  • Practice safe travel habits: expose only one person at a time, have an escape route planned, watch your buddies closely and view slopes as avalanche paths. If the snow does slide, where will it go? Avoid terrain traps. 

Snow pit on Sunburst January 8th and a snow pit from Seattle Ridge on January 7th. These illustrate the weak layers of snow in the snowpack under a slab, that in both spots the snowpack is still reactive and that an avalanche may be triggered.


Avalanche Problem 2

Deep Persistent Slabs

Almost Certain
Very Likely


Very Large


Deep Persistent Slabs have been in the forecast every day starting December 14th. Because a poor snowpack structure still exists at high elevations above 3,000’, human triggered large and dangerous, deep slab avalanches are still possible. Weak sugary snow (basal facets) near the ground is creating a low probability/high consequence avalanche problem. Likely trigger spots will be in thinner areas of the snowpack that are connected to large, loaded slopes. Signs of instability will not likely be present and there may be tracks on the slope. The possibility of a deep slab avalanche should still be part of your decision-making before committing to big terrain in the Alpine. 

Additional Concern

Dry Loose

Cold temperatures are continuing to weaken the surface snow. Observers in the Turnagain area yesterday noted this. Sluffs (loose snow avalanches) are getting larger and could catch you off guard in steep terrain. 



Mountain Weather

Yesterday was mostly clear above the valley fog. The fog did not move out contrary to the morning forecast. Temperatures were in the teens to single digits with a minor inversion. Winds were easterly 5-15 with gusts in the high teens. 

Today will be partly to mostly cloudy and there is a chance of snow showers this afternoon. Temperatures will warm into the high teens, low 20s. Winds will be easterly 5-15 with gusts into the 20s. Snow showers will continue overnight with a chance of 1-2" of accumulation. Easterly winds will pick up this evening gusting into the 30s and temperatures will be in the teens to low 20s. 

The pattern for the next few days sets up with warmer air and a series of storms on track to impact the area. Stay tuned for timing, precipitation amounts and temperatures. 

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

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880')  18  0  0 43 
Summit Lake (1400')  7  0   0 15 
Alyeska Mid (1700') 14   0  0 35 


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

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812') 11   E  19
Seattle Ridge(2400') 15 SE   12  16

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 15, 2018 )

Glacier District
Johnson Pass: Open
Placer River: OpenPlease avoid private property and AKRR job site at Luebner Lake. Cross railroad tracks if needed, do not ride down tracks, it is illegal.
Skookum Drainage: OpenCross railroad tracks if needed, do not ride down tracks, it is illegal. FYI, Skookum drainage closes to Snowmachines on 4/1 as per the Chugach NF plan.
Turnagain Pass: Open
Twentymile: OpenCross railroad tracks at designated spot as you leave the parking area.
Seward District
Carter Lake: Open
Lost Lake Trail: Open
Primrose Trail: Open
Resurrection Pass Trail: OpenResurrection Pass trail is open to snowmachine use during the 2017/18 winter season.
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.

If you have comments or questions regarding CNFAIC operations or winter recreation management, please email
© 2018 Chugach National Forest Avalanche Information Center. All rights reserved.