Turnagain Pass RSS

Archives
ARCHIVED - Forecasts expire after 24 hours.
Issued
Wed, February 4th, 2015 - 7:00AM
Expires
Thu, February 5th, 2015 - 7:00AM
Forecaster
Heather Thamm
Avalanche risk The Bottom Line

A LOW avalanche danger exists over most of Turnagain Pass, with pockets of MODERATE danger on wind exposed areas of the forecast zone. Old wind slabs 8-10 € can be triggered if found on slopes steeper than 40 °.    

Special Announcements

Attention Ladies: SheJumps, CNFAIC, and Alyeska Resort are joining forces to host a 2 hour avalanche companion rescue clinic at Alyeska Resort on Sunday, Feb.8 from 1pm-3pm. This is a free clinic for ladies only, and is a great place to practice your beacon skills. Click HERE for more info.

Wed, February 4th, 2015
Alpine
Above 2,500'
1 - Low
Avalanche risk
Treeline
1,000'-2,500'
1 - Low
Avalanche risk
Below Treeline
Below 1,000'
0 - No Rating
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
  • Normal Caution
    Normal Caution
Normal Caution
Normal Caution means triggering an avalanche is unlikely but not impossible.
More info at Avalanche.org

Today looks like a continuation of this week’s theme movie, Groundhogs Day. For those getting out into the mountains expect another day of sunny clear skies with relatively mild temperatures (20’s F) above 1000’. Over the last week this inverted weather pattern has been allowing backcountry skiers and riders to push further into the periphery of our forecast zone. In the Turnagain Pass area a mostly LOW avalanche danger exists, but there is still potential to find pockets of unstable snow. These pockets will be more likely in terrain steeper than 40° specifically in places that have had more wind exposure to create a slab 8-10″ thick on top of weak snow. 

Old Wind Slabs

A few days ago two skiers triggered an isolated pocket of surface snow while boot packing up a steep Eastern convexity in the Seattle Creek drainage at about 2400’. This isn’t too surprising due to the fact much of the surface snow, top 3-6”, has been loosing strength over the last two weeks due to clear skies and cool temperatures. At mid elevations, below 3000’ a crust layer sits below this weak “faceted” snow creating the perfect environment for localized winds to form a slightly denser slab above. Pay attention to the consistency of the surface snow. If you find yourself in snow where the surface is stiff on top or feels hollow, watch your slope angles. 

At higher elevations above 4000’ a crust/facet combo has been found in thinner areas of the snowpack. This weak layer/bed surface combination showed potential to propagate a slab 10–12” thick in a test pit near the Girdwood Valley. Be extra careful in steep terrain around rocks or convex terrain features where the snowpack is thinner. 

Loose Snow

Cold temperatures and clear skies have continued to make much of the surface snow weak and poorly bonded. In general this is a low hazard, but if riding or skiing on slopes steeper than 40° pay attention. Loose snow with enough volume and momentum can knock you off your feet.

 

Recent sluffing from ski tracks on a Northern aspect where the surface snow is weak and poorly bonded.  

Sun Exposure

Believe it or not the sun has had enough radiation to affect the surface snow on Southern aspects. Several days ago this produced some small damp loose-snow avalanches, but cold evening temps have strengthened this into a crust leaving a thin breakable layer behind. Today the sun warrants an additional concern for any fair skinned creatures such as myself. Sunglasses and sunscreen might be a good idea while clear skies continue throughout the week.

Weather
Wed, February 4th, 2015

Near sea level yesterday’s inverted air kept temperatures slightly cooler (teens F) under a low valley fog.  Above 1000′ temperatures were in the low 20’sF with relatively calm winds. Inland, near Summit Lake, temperatures were in the single digits on shaded areas of the valley floor. No new precipitation has been recorded for the last four days.

Today looks very similar with sunny skies and dense patches of valley fog near sea level. Temperatures look to remain warmer during the day (teens to low 20’s F) but dropping into single digits into the evening. Light winds out of the Northwest are expected at higher elevations.  

Expect more clear, dry, cold weather throughout the week. There has been some discussion about the high pressure over Alaska’s interior combining with a low pressure in the Southeast Gulf creating a tighter pressure gradient later in the week. In other words we could be feeling colder temperatures and strong Northwest winds in Southcentral Alaska near the end of the week.  

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

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880′) 20   0   0   32  
Summit Lake (1400′) 7   0   0   7  
Alyeska Mid (1700′) 20   0   0   20  

RIDGETOP 24-hour data (6am – 6am)

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812′) 21   W   3   10  
Seattle Ridge (2400′) 20   Var.   3   8  
Observations
Recent Observations for Turnagain Pass
Date Region Location
05/13/24 Turnagain Observation: Eddie’s, Sunburst, Seattle, Cornbiscuit, Pete’s South
05/13/24 Turnagain Observation: Turnagain Pass non-motorized side
05/12/24 Turnagain Observation: Warm up Bowl
05/07/24 Turnagain Observation: Turnagain Pass Wet Slabs
04/29/24 Turnagain Avalanche: Turnagain aerial obs
04/27/24 Turnagain Observation: Johnson Pass
04/23/24 Turnagain Observation: Turnagain Sunny Side
04/21/24 Turnagain Observation: Bertha Creek
04/20/24 Turnagain Avalanche: Spokane Creek
04/16/24 Turnagain Observation: Cornbiscuit
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.