Avalanche Advisory

Turnagain Area Avalanche Advisory
Tuesday, November 28th 2017 4:18 am by Aleph Johnston-Bloom
ARCHIVED ADVISORY - All advisories expire after 24 hours from the posting date/time.
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The Bottom Line


The avalanche danger is MODERATE on all slopes near and above treeline. Triggering a slab avalanche 1' thick is possible today on steep slopes that have recently been loaded by winds. New snow is falling on a variety of surfaces that it may not bond well to. Pay attention to changing conditions as more snow (and/or rain) falls, temperatures rise and winds increase. 

*Below Treeline: ICE CLIMBERS in Portage Valley: Small avalanches today, and growing in size this week, could release naturally in higher terrain, sending debris over climbing routes. 

 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.
Special Announcement

Motorized use on Turnagain Pass is closed due to insufficient snow cover.  Please see riding area status at the bottom of this page for the most up-to-date information.

Snowmachine Specific – Avalanche Safety and Lessons Learned at AMDS, December 5th @ 6:30 pm - 8:00 pm | FREE Join CNFAIC forecasters at Alaska Mining and Diving Supply for a talk about lessons learned from past avalanche events and get your brain in gear for avalanche season.

The CNFAIC Events Calendar is filling up with avalanche education opportunities. Check it out and find a class that is right for you! 

**For Hatcher Pass avalanche conditions see

Avalanche Problem 1

The advisory area received a few inches of additional snow in the last 24 hours and more is on tap today and tonight. Temperatures have risen and the snowline is forecasted to rise to 1000'. Precipitation that falls today and tonight will be heavier/wetter than yesterday. Warm, wet snow over cold dry snow may form storm slabs.  New snow combined with easterly winds gusting into the 40s will add to the potential for wind slabs on leeward slopes. Steep (35+ degrees) unsupported slopes will be the most suspect for triggering new or old wind slabs.  If you do venture out today it will be important to pay attention to drifting, look for cracking and listen for hollow sounds and/or whumpfing. 

Determining whether or not new snow is bonding to old snow surfaces will be the question in the next few days. Remember this snow is falling on variety of surfaces including crust, facets, old wind effected snow or grass and rocks. Getting pulled down by even a small slab could have a very rough ride due to rocks and thin snow cover. 

If rain falls on the new snow in Portage Valley wet loose avalanches will be possible in ice climbing terrain. 

Image of the melt freeze crust covering most of the terrain above approximately 1600'. The main concern is where the crust is underneath weak faceted snow that will be covered up in the next few days.  The weak faceted snow is our greatest concern for future snow load as it will likely inhibit the new snow from bonding and the crust could be a slippery bed surface. 


Mountain Weather

Yesterday light snow fell in the morning and tapered off in the afternoon. Turnagain picked up a few inches and Girdwood added another inch to what had fallen overnight.  Temperatures rose to above freezing at Center Ridge, 1880' on Turnagain Pass. Winds were easterly gusting into the 40s.  

Today will be cloudy with another 1-4 inches of snow forecasted to fall with a chance of rain up to at least 1000'. Winds will be easterly again 10-20mph gusting into the 40s. Expect temperatures in the mid 20Fs at upper elevations to mid 30Fs at sea level. Tonight precipitation will increase, 4-8 inches of snow possible with rain/snow mix at low elevations, and the easterly winds will continue with gusts bumping into the 50s.  

Tomorrow rain/snow showers will continue and winds should decrease in the afternoon. Temperatures will stay warm until the evening as this system moves out of the area. 

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

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880') 33   3 .3   12
Summit Lake (1400') 29  1  .1  7
Alyeska Mid (1700')  31  1  .1  7 


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

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812')  22 ENE  18  45 
Seattle Ridge(2400') 25  Sensor Rimed  Sensor Rimed  Sensor Rimed 

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.