Mon, April 04, 2016 Turnagain Pass Avalanche Forecast

Mon, April 4th, 2016

Alpine
Above 2,500'

Low (1)

Treeline
1,000'-2,500'

Considerable (3)

Below Treeline
Below 1,000'

No Rating (0)

Alpine Above 2,500'		Low (1)
Treeline 1,000'-2,500'		Considerable (3)
Below Treeline Below 1,000'		No Rating (0)

Danger Scale:

No Rating (0)

Low (1)

Moderate (2)

Considerable (3)

High (4)

Extreme (5)

Avalanche Problem 1

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

Glide avalanches remain our primary concern in the Turnagain Pass and surrounding regions. Although the snowpack is stable itself, how it is sticking to the sides of the mountins is another thing. On all aspects at elevations below 3,000′ the snowpack, as a whole, continues to ooze down the slopes and create cracks (despite having a hard crust on the surface). Every now and again one of these cracks will release into a full-depth avalanche. There is no way to predict when a crack is going to release. What we do know is the frequency of glide avalanches is on the rise. Since Friday (4/1) five large glide avalanches occurred on Seattle Ridge and several others between Girdwood and Summit Lake. Read the reports from over the weekend HERE.

The reason this is so alarming is that new glide cracks are appearing daily and many threaten popular terrain. The Seattle Ridge uptrack is one of our biggest concerns because a large crack now puts this popular route in the line of fire. If you were to be in the wrong place at the wrong time you would not survive a glide avalanche. High marking or setting a skin track under a glide crack is not recommended!

Heather showed the photos below yesterday but they are too good not to post again today as today’s concerns are the same. Please ‘thread the needle’ carefully as you move through these mid-elevations.

Avalanche Problem 2

Normal Caution

Normal Caution

Normal Caution means triggering an avalanche is unlikely but not impossible.

More info at Avalanche.org

Other than the scary glide avalanche issue we have a normal caution in the backcountry. The snowpack is stable and sports a solid crust on the surface. Sunshine yesterday softened the surface enough for bone fide springtime corn skiing by the afternoon. On slopes the sun is not warming, there is ‘slide for life’ potential as the surface crust is very slippery. For today, high clouds may limit surface warming – but then again, the sun has a way of poking out in places.

Cornices? We are still waiting for the Alpine to warm up enough to start seeing natural cornice falls. These giant features are still holding on and looming.

Weather

Mon, April 4th, 2016

Sunny skies and warm temperatures greeted many backcountry travelers yesterday. Ridgetop winds were light from the East and downright calm on some ridgelines. Temperatures reached the mid 40’s F in the parking lots and the upper 20’s F on the ridgetops.

For today we are expecting some high clouds fill in as a frontal band associated with a low pressure just South of the Aleutians heads our way. Winds are expected to increase to the 10-20mph range from the East on the ridgetops and a trace of snow is possible above 1,000′ with a chance for a raindrop or two below 1,000′.

Tonight into Tuesday we should see the low pressure system move through with light precipitation (rain/snow line ~1,000′) and accumulation in the 1-3″ range. Stay tuned.

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

	Temp Avg (F)	Snow (in)	Water (in)	Snow Depth (in)
Center Ridge (1880′)	34	0	0	118
Summit Lake (1400′)	32	0	0	37
Alyeska Mid (1700′)	34	0	0	104

RIDGETOP 24-hour data (6am – 6am)

	Temp Avg (F)	Wind Dir	Wind Avg (mph)	Wind Gust (mph)
Sunburst (3812′)	25	NE	9	22
Seattle Ridge (2400′)	28	SE	8	24

Observations

Recent Observations for Turnagain Pass

Date	Region	Location	Observer
05/22/23	Turnagain	Avalanche: Tincan	Nick D'Alessio
05/12/23	Turnagain	Avalanche: Tincan, Sunburst, Magnum, Cornbiscuit	Heather Thamm
05/07/23	Turnagain	Observation: Tincan – Bear Tracks	CNFAIC Staff
05/05/23	Turnagain	Observation: Seattle Ridge	AS/ WW Forecaster
05/02/23	Turnagain	Observation: Cornbiscuit	Schauer/ Sturgess Forecaster
05/02/23	Turnagain	Observation: Seward Hwy Turnagain Pass	Joel Curtis
04/30/23	Turnagain	Observation: Magnum	Ayla, Kit Crosby, Barton
04/29/23	Turnagain	Observation: Tincan	John Sykes
04/28/23	Turnagain	Avalanche: Taylor Pass/Pastoral	Schauer/ Creighton Forecaster
04/28/23	Turnagain	Avalanche: Tincan	Andy Moderow

Riding Areas

Updated Thu, June 01st, 2023

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 May 15.
Placer River	Closed	Closed May 15.
Skookum Drainage	Closed	Will close to motorized use on April 1, 2023 per the National Forest Plan.
Turnagain Pass	Closed	Will close on June 1.
Twentymile	Closed	Scheduled closure May 1.
Seward District
Carter Lake	Closed	Scheduled closure May 1.
Lost Lake Trail	Closed	Scheduled closure May 1.
Primrose Trail	Closed	Scheduled closure May 1.
Resurrection Pass Trail	Closed	Closed to motorized use for the 2022/23 winter season per Forest Plan. Open next season.
Snug Harbor	Closed	Extended opening until May 15.
South Fork Snow River Corridor	Closed	Scheduled closure May 1.
Summit Lake	Closed	Scheduled closure May 1.