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Avalanche Advisory

Turnagain Area Avalanche Advisory
Forecaster:   Wendy Wagner  
Tuesday, January 28th 2014
Created: Jan 28th 6:42 am
3 Considerable Alpine / Above 2,500' Travel Advice: Dangerous avalanche conditions. Careful snowpack evaluation, cautious routefinding and conservative decision-making essential.
3 Considerable Treeline / 1,000'-2,500' Travel Advice: Dangerous avalanche conditions. Careful snowpack evaluation, cautious routefinding and conservative decision-making essential.
3 Considerable Below Treeline / Below 1,000' Travel Advice: Dangerous avalanche conditions. Careful snowpack evaluation, cautious routefinding and conservative decision-making essential.
 Show the Complete North American Avalanche Danger Scale
Special Announcement

There are only a few days left to apply for the Rob Hammel Scholarship Fund. This is an avalanche education scholarship sponsored by The Friends of the CNFAIC and the Rob Hammel family. This is a great opportunity. Deadline to apply is January 31st.  Go to this page for more information.  


The Bottom Line

We have a CONSIDERABLE avalanche danger both above and below treeline. With continued unseasonably warm and wet conditions the possibility remains for large wet slab and/or deep slab avalanches to release. These have been full-depth slides consisting of heavy wet snow that can run to valley bottoms. Though the likelihood is decreasing with time and cooler temperatures today the consequences remain high. Steering clear of avalanche terrain and runout zones continues to be prudent.

There is very little to no snow below 1,000'. The danger at this elevation is from above where an avalanche releasing could deposit debris in runout areas and gullies. 


Primary Concern

Despite the impressive spike in temperature yesterday at the ridgetops, we did not see or hear of any new avalanche activity. There were a few small wet point releases and one potential small slab in the Summit Lake area that may have occurred. Our last known wet slab was on Turnagain Pass Sunday - two days ago. Photo below.

One thing we have different today is a substantial drop in temperature. This is good news, both for stabilizing the snowpack as well as limiting the melt-out seen below treeline. However, temperatures are still warm in the big picture and though the snowpack continues to season and adjust to the warm conditions, large wet avalanches are still possible. 

Below is the last known wet slab avalanche. It occurred Sunday, January 26th on Pete's South ridge - South side of Turnagain Pass.


Secondary Concern

At the upper elevations (above 3,500' or so) where snow has been falling for almost two weeks now the snowpack has been getting deeper by the day. We had evidence of a large deep slab avalanche cycle last week, with the last known deep slab three days ago on Goat Mtn. Though it has been a few days since we've seen or heard of any new deep slabs, it doesn't mean the problem has gone away. The pack dealt with a large spike in temperature yesterday (over 40F at 4,200') and has seen persistent strong wind for over a week. It is not likely anyone will be traveling in this upper elevation terrain, but the possibility exists for natural avalanches to occur and run to valley bottoms.


Additional Concern

A few comments on the state of the snowpack:

  • Below treeline - the pack is completely wet, unsupportable (mush) and melting out. The Turnagain Pass SNOTEL at 1880' is reporting 29" depth (average for the past nine years of available data is 73"). Click here for a few more details and pictures
  • Above treeline - the pack starts with around 40" of wet snow at treeline and becomes much deeper and dryer with elevation. Around 4,000' and higher the snow is dry enough that wind is able to produce plumes.

All that said, there is still a layer of weak faceted snow that sits near the ground and is responsible for our many slab avalanches seen so far this season. Depending on elevation, the faceted snow is either wet (below treeline) and melting or dry (well above treeline) and being compressed with the weight of the new snow from the past couple weeks.

Below treeline (Turnagain Pass looking Northeast)              Above treeline (South end of Pass looking North at Pk 4940)
    


Mountain Weather

During the past 24-hours we have seen a significant drop in temperature since yesterday morning's spike (to the low 40's F on the ridgetops and mid 50's at sea level). We are now sitting in the upper 20's at the ridgetops and around 40F at sea level. Winds were averaging 50mph yesterday but have dropped to 10mph overnight from the East. We had .4" of rain to 3,500', mostly falling in the afternoon.

Today we should see the remnants of yesterday's system move out. Light rain up to 1,500' is expected to fall during the day with around .2" accumulating. Skies should be mostly cloudy and could clear up a bit by the afternoon. Temperatures will be in the upper 20's on the ridgelines and near 40F at sea level. Winds are expected to remain light from the East in the 10mph range.

For tomorrow we should see conditions similar to today but for Thursday a cooling and clearing trend looks to develop. 

 

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 28, 2017 )

AREA STATUS WEATHER AND RIDING CONDITIONS
Glacier District
Johnson Pass: Closed
Placer River: Closed
Skookum Drainage: ClosedSKOOKUM DRAINAGE CLOSED TO MOTORIZED USE ON APRIL 1 annually as per the Chugach National Forest Plan document.
Turnagain Pass: OpenOpen thru May 14th.
Twentymile: Closed
Seward District
Carter Lake: OpenClosed May 1.
Lost Lake Trail: OpenClosed May 1.
Primrose Trail: OpenClosed May 1.
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: OpenClosed May 1.
South Fork Snow River Corridor: OpenClosed May 1.
Summit Lake: OpenClosed May 1.

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
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