Turnagain Pass RSS

Archives
ARCHIVED - Forecasts expire after 24 hours.
Issued
Wed, December 9th, 2015 - 7:00AM
Expires
Thu, December 10th, 2015 - 7:00AM
Forecaster
CNFAIC Staff
Avalanche risk The Bottom Line

The avalanche danger is MODERATE  in the Alpine.  Winds that blew Monday night into Tuesday morning have created shallow slabs in leeward areas. The most suspect slopes are in steep terrain at the high elevations where the winds have deposited additional snow.  

Look for changing conditions as snow and wind impact the advisory area today and tomorrow.

At Treeline and below the danger is LOW.

*If venturing into the ‘periphery’ forecast zones, such as Girdwood Valley, Silvertip and Summit Lake areas, more caution is advised due to limited information about the snowpack in these areas.

Special Announcements

Fireside Chat #2 – Avalanche Rescue – Dec 10th!!  Join CNFAIC forecaster Heather Thamm Thursday night from  6:30-8:00pm at the Alaska Avalanche School  for a presentation on “Rescue Fundamentals”. A successful rescue of a buried individual can hinge on even a little bit of knowledge, we hope to see you there! This class is great introduction if you are new to the topic and a terriffic way to refresh your understanding if you have taken a class before!

Interested in how people make decisions in avalanche terrain?  Montana State University’s Snow and Avalanche Laboratory, is leading a project they hope will bring about a better understanding of those risk-taking decisions with a smartphone app. Check out yesterday’s article in ADN to learn how it works, how you can participate and help collect Alaskan data!

Wed, December 9th, 2015
Alpine
Above 2,500'
2 - Moderate
Avalanche risk
Treeline
1,000'-2,500'
1 - Low
Avalanche risk
Below Treeline
Below 1,000'
1 - Low
Avalanche risk
0 - No Rating
1 - Low
2 - Moderate
3 - Considerable
4 - High
5 - Extreme
Avalanche risk Avalanche risk Avalanche risk Avalanche risk Avalanche risk
Travel Advice Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern. Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding, and conservative decision-making essential. Very dangerous avalanche conditions. Travel in avalanche terrain not recommended. Extraordinarily dangerous avalanche conditions. Avoid all avalanche terrain.
Likelihood of Avalanches Natural and human-triggered avalanches unlikely. Natural avalanches unlikely; human-triggered avalanches possible. Natural avalanches possible; human-triggered avalanches likely. Natural avalanches likely; human-triggered avalanches very likely. Natural and human-triggered avalanches certain.
Avalanche Size and Distribution Small avalanches in isolated areas or extreme terrain. Small avalanches in specific areas; or large avalanches in isolated areas. Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas. Large avalanches in many areas; or very large avalanches in specific areas. Very large avalanches in many areas.
Avalanche Problem 1
  • Wind Slabs
    Wind Slabs
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
More info at Avalanche.org

The sustained winds from Monday night into Tuesday morning changed the snow conditions in the Alpine. Observers reported pockets of wind slab and scoured ridgelines. While traveling today look for areas that have had recent loading and avoid stiff snow in steep terrain. Watch for cracking and listen for hollow sounds that could indicate the shallow wind slabs may be reactive. 

The Turnagain Pass area received an inch of snow yesterday and more is forecasted for today and tonight. Pay attention to changing conditions and expect avalanche danger to increase as we load up the weak surface snow that formed during the period of high pressure and low danger. 

What has changed or is changing? These should be the questions in the next few days. Look for Red Flags: recent avalanches, cracking, whumfing, recent snowfall and signs of recent wind. These signs of instability indicate heightened avalanche danger and the need for cautious travel behavior. 

Good travel habits, such as exposing one person at a time, watching your partners, grouping up in safe zones and having an escape route planned are, as always, key ways to minimize risk. 

Wind effect and rime crust on Big Chief. Photo: Billy Finley

Weather
Wed, December 9th, 2015

The low in the Gulf is impacting the forecast area today. Skies will be cloudy with snow showers likely throughout the day.  New snow accumulation of 1 to 3 inches is possible. Highs will be in the mid 20Fs to upper 30Fs. Winds will be variable from the North.  

Snow will continue tonight with an addtional 3-6 inches possible. There is more unsettled weather and snow on tap for later in the week as the pattern continues to push a series of lows into the region.  

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

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880′) 27    1 .1    23
Summit Lake (1400′)  25 0    0 11  
Alyeska Mid (1700′) 24    0  0  18

RIDGETOP 24-hour data (6am – 6am)

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812′) 26    NE 7   22  
Seattle Ridge (2400′)  26 NE-SE    7  13
Observations
Recent Observations for Turnagain Pass
Date Region Location
03/27/24 Turnagain Observation: Tincan Trees
03/26/24 Turnagain Observation: Cornbiscuit
03/25/24 Turnagain Observation: Tincan
03/22/24 Turnagain Avalanche: Magnum Northwest Aspect
03/21/24 Turnagain Observation: Sunburst
03/21/24 Turnagain Observation: Tincan Proper North Aspect
03/20/24 Turnagain Avalanche: Seattle Creek Drainage
03/19/24 Turnagain Observation: Tincan CFR
03/18/24 Turnagain Avalanche: Tincan – Eddies – Seattle Ridge
03/18/24 Turnagain Observation: Tincan
Riding Areas

The riding areas page has moved. Please click here & update your bookmarks.


Subscribe to Turnagain Pass
Avalanche Forecast by Email

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.