Turnagain Pass RSS

Archives
ARCHIVED - Forecasts expire after 24 hours.
Issued
Fri, February 28th, 2014 - 7:00AM
Expires
Sat, March 1st, 2014 - 7:00AM
Forecaster
John Fitzgerald
Avalanche risk The Bottom Line

The avalanche hazard is MODERATE above and below treeline today.   Wet loose avalanches will be easily triggered in steep terrain.   It will also be possible for humans to trigger wet slabs up to 3 feet in depth today.

Travel on snow may be difficult, epsecially in the lower elevations where the snow surface is not consistently supportable.   Avoiding terrain 40 degrees and above at all elevations will be the best way to manage these avalanche hazards today.

Special Announcements

Please consider participation in this short survey at  http://edu.surveygizmo.com/s3/1523144/Avy  if  you recreate in Turnagain Pass.  Your feedback will help assist in avalanche forecasting and avalanche education while contributing to ongoing research that benefits the backcountry community.  Participants will be entered into a prize drawing and have access to final results!

Fri, February 28th, 2014
Alpine
Above 2,500'
2 - Moderate
Avalanche risk
Treeline
1,000'-2,500'
2 - Moderate
Avalanche risk
Below Treeline
Below 1,000'
2 - Moderate
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
  • Wet Loose
    Wet Loose
Wet Loose
Wet Loose avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
More info at Avalanche.org

Another day of above freezing temperatures will keep the likelihood for wet loose avalanches on the high end of the scale.  Terrain above 40 degrees at all elevations holds the potential for humans to easily trigger slow moving wet sluffs.  On their own, these avalanches will not have quite enough volume to bury a person.  That all changes if you are carried through trees, over cliff bands or into gullies & depressions.  Be aware of and learn how to recognize terrain traps.  Traveling in big terrain where multiple paths converge is another area where the volume of wet loose avalanches can and will increase.  Avoiding being on or in the runout of steep slopes in cirques and bowls will minimize your exposure to more dangerous (higher volume) wet loose avalanches today.

While it has been warm lately, we have not seen any wet slab activity.  A lack of water moving into deeper weak layers in the snowpack has helped to prevent these more dangerous types of avalanches from occurring.  While this has been the case, the possibility still remains for wet slab avalanches, up to 3’ in depth, to pull out in steep terrain.  Steep sunlit slopes and areas where the overall snowpack is thinner are spots to avoid today.

Avalanche Problem 2
  • Cornice
    Cornice
Cornice
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
More info at Avalanche.org

Snow and wind has helped to build up cornices over the past month.  Warm temps and sunshine today will warrant the need to steer clear of cornices.  It is always worth staying off of these behemoths.  Knowing where the snow connects to the underlying terrain is important in being able to effectively avoid punching through or triggering a cornice onto an underlying slope.

Weather
Fri, February 28th, 2014

Temperatures over the past 24 hours have dipped slightly but still remain warm.

Seattle Ridge (2,400′) at 6am: 32 F                       Sunburst (3,812′) at 6am: 30 F
Seattle Ridge max 24 hr temp: 40 F                         Sunburst max 24 hr temp: 39 F

Winds at Sunburst have been light mainly out of the East.   No measurable precipitation fell, though light rain was observed during the day yesterday.

Today expect an occasional light rain shower in the morning with clearing skies as the day progresses.   Temps at 1,000′ will be in the high 30s F.   Winds will be very light out of the Southeast.

The extended outlook is calling for clear skies and gradually cooling temps as we head into the weekend.   The next chance for snow looks to be in the early part of next week.

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.