Turnagain Pass Avalanche Forecast RSS

Archives
ARCHIVED FORECAST - All forecasts expire after 24 hours from the posting date/time.
Issued
Fri, January 22nd, 2016 - 7:00AM
Expires
Sat, January 23rd, 2016 - 7:00AM
Forecaster
Aleph Johnston-Bloom
The Bottom Line

Today a  MODERATE  avalanche danger exists in the Alpine and at Treeline. Triggering an isolated wind slab is possible on steep wind-loaded features. In places protected from the wind, loose snow avalanches could be fast moving and easily knock you off your feet in steep terrain. In the mid-elevation band (at Treeline), glide cracks pose a significant threat as they continue to grow and release. Avoid travel underneath them.

A  LOW  avalanche danger exists below 1000′ where triggering an avalanche is unlikely.

If you are thinking of going to Summit Lake, be aware that different avalanche problems exist within the snowpack. Click  HERE  to read the Summit Lake Summary from this last weekend.  

Thanks to our sponsors!
Fri, January 22nd, 2016
Alpine
Above 2,500'
Moderate (2)
Avalanche risk
Treeline
1,000'-2,500'
Moderate (2)
Avalanche risk
Below Treeline
Below 1,000'
Low (1)
Avalanche risk
Alpine
Above 2,500'
Avalanche risk
Moderate (2)
Treeline
1,000'-2,500'
Avalanche risk
Moderate (2)
Below Treeline
Below 1,000'
Avalanche risk
Low (1)
Danger Scale:
No Rating (0)
Low (1)
Moderate (2)
Considerable (3)
High (4)
Extreme (5)
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

Wind slabs: Over the last few days several wind events combined with over a foot of new snow have created wind slabs up to 20” thick on leeward features. The good news is this new snow seems to be bonding well with the old snow below, however not enough time has passed for this hazard to have completely healed. Yesterday we received reports of skiers triggering pockets of wind slab on steep wind-loaded slopes. Trigging an isolated wind slab in the wrong place, like over a cliff or above a terrain trap, could have high consequences. As wind slabs get older they get stiffer and may allow for travel out onto them before they release. Watch for shooting cracks and avoid hollow sounding snow.

Cornices: Already large cornices have received additional stress from the new snow load and strong winds earlier in the week. These have a tendency to break farther back than expected and can send you for an undesirable ride.  Approach ridgelines with caution and avoid being on or directly below cornices features. 

Image from FS National Avalanche Center.

 

Avalanche Problem 2
  • Dry Loose
    Dry Loose
Dry Loose
Dry Loose avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.
More info at Avalanche.org

In places protected by the wind 12” of loose unconsolidated snow could be fast moving in steep terrain. Loose snow can easily knock a person off of their feet or take them for a ride over a cliff or into a terrain trap. Manage your ‘sluff’ and avoid terrain features with high consequences. Skiers have reported being surprised by these conditions over the past couple days. 

 

Additional Concern
  • Glide Avalanches
    Glide Avalanches
Glide Avalanches
Glide Avalanches are the release of the entire snow cover as a result of gliding over the ground. Glide avalanches can be composed of wet, moist, or almost entirely dry snow. They typically occur in very specific paths, where the slope is steep enough and the ground surface is relatively smooth. They are often proceeded by full depth cracks (glide cracks), though the time between the appearance of a crack and an avalanche can vary between seconds and months. Glide avalanches are unlikely to be triggered by a person, are nearly impossible to forecast, and thus pose a hazard that is extremely difficult to manage.
More info at Avalanche.org

Today at Treeline (the 1,000’ – 2,500’ elevation band) on all aspects, pay attention to and AVOID glide cracks. These can lead to glide avalanches that are very unpredictable as we have seen over the past few days. Yesterday there was a large release on the South face of Sharks Fin. The cracks on Corn Biscuit were recently observed and continue to grow.  There is no discernable pattern to predict a failure, as they tend to fail naturally and on their own schedule. Warm temperatures can trigger them and so can cooling temperatures. Cracks can form and release in seconds or days later or sometimes a glide crack won’t release at all. The new snow has made it harder to see the existing cracks and glide releases in the terrain. 

It is best to give glide cracks a wide berth.  AVOID spending time underneath and if skiing or riding in terrain with glide cracks, try and map them out before your travels so as not to end up directly on top of or inside one.  Remember, when these do fail, they tend to be destructive, failing to the ground and bringing the entirety of the snowpack with them.

Don’t mess with the ‘Brown Frown’!!!

 

Weather
Fri, January 22nd, 2016

Yesterday was mostly cloudy with light Northeasterly winds. Temperatures were in the mid-20Fs with a warming trend overnight.

Today will be mostly cloudy with a mix of rain and snow showers, 1-3 inches of snow accumulation is possible. Winds will be easterly 10-20 mph. Temperatures will be in the mid-20Fs to mid-30Fs. Snow showers will continue overnight with an additional 2-4 inches of snow forecasted and a slight increase in winds.  

A series of low-pressure systems are lining up to impact the area over the weekend and into next week. The NWS is calling this a ‘Parade of Lows’. Expect rain/snow showers and winds to increase as these systems move through.  

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

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880′)  28 0   0   86  
Summit Lake (1400′)  28 0   0 27  
Alyeska Mid (1700′)  29 0   0 67

RIDGETOP 24-hour data (6am – 6am)

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812′)  27 ENE   10   25  
Seattle Ridge (2400′) 25 n/a   n/a   n/a  
Observations
Recent Observations for Turnagain Pass
Date Region Location
12/10/19 Turnagain Avalanche: Tincan and Sunburst from the air
12/10/19 Turnagain Observation: Tincan
12/08/19 Turnagain Avalanche: Tincan
12/06/19 Turnagain Avalanche: Sunburst
12/04/19 Turnagain Observation: Sunburst
12/03/19 Turnagain Observation: Hippy Bowl
12/01/19 Turnagain Observation: Tincan, All elevations
12/01/19 Turnagain Observation: Tincan
11/30/19 Turnagain Observation: Tincan Treeline Plateau/ Common Bowl/ Ridge
11/29/19 Turnagain Observation: Sunburst Ob #2
Riding Areas
Updated Wed, December 11th, 2019

Status of riding areas across the Chugach NF is managed by the Glacier and Seward Ranger Districts, not avalanche center staff. Riding area information is posted as a public service to our users and updated based on snow depth and snow density to prevent resource damage at trailhead locations. Riding area questions contact: mailroom_r10_chugach@fs.fed.us

Area Status Weather & Riding Conditions
Glacier District
Johnson Pass
Closed
Closed.
Placer River
Closed
Closed.
Skookum Drainage
Closed
Closed.
Turnagain Pass
Closed
Closed.
Twentymile
Closed
Closed.
Seward District
Carter Lake
Closed
Closed.
Lost Lake Trail
Closed
Closed.
Primrose Trail
Closed
Closed.
Resurrection Pass Trail
Closed
Closed. Will be open for the 2019/20 season pending adequate snow cover.
Snug Harbor
Closed
Closed.
South Fork Snow River Corridor
Closed
Closed.
Summit Lake
Closed
Closed.

Subscribe to Turnagain Pass
Avalanche Forecast by Email