Thu, March 12, 2015 Turnagain Pass Avalanche Forecast

Thu, March 12th, 2015

Alpine
Above 2,500'

Low (1)

Treeline
1,000'-2,500'

Low (1)

Below Treeline
Below 1,000'

No Rating (0)

Alpine Above 2,500'		Low (1)
Treeline 1,000'-2,500'		Low (1)
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

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

Lingering wind slabs from the strong Northwest winds earlier this week are littered about the mountains. They can be found to be a few inches thick to a foot thick. They vary from stiff and supportable to breakable and in some areas, still on the softer side. These slabs are a concern in steep complex terrain where even a small plate can knock you off your feet and pitch you somewhere you don’t want to go. One of my partners triggered one of these old pockets yesterday (a soft old wind slab ~10″ thick and 20′ wide in steep terrain photo below).

Avalanche Problem 2

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

Sluffs are VERY easy to trigger in steep terrain harboring loose surface snow. These are running faster and farther each day as the snow is becoming looser and looser with the cold weather. Sluff management is key. This means know where your sluff will go and stay out of the way of the debris. The volume of these sluffs is on the moderate side but, still plenty to washing-machine someone if caught on a sustained slope.

SEE VIDEO HERE. Photo above by John Sykes: Sluffs triggered in the Gold Pan basin yesterday (behind the Magnum and Cornbiscuit ridges and near the top of Bertha Creek)

As Heather mentioned yesterday, there is some great skiing and riding to be had at the Pass. Honing in on the dappled surface texture (or orange peel as some say) to suss out the soft snow works well. Also, despite the continued hazardous approaches from the parking lots, there is now a “Tincan Rappel” which makes accessing the goods on Tincan easier – thanks to the helpful citizen for the installation!

Additional Concern

Dry Loose

More info at Avalanche.org

Additional concerns include the

Weather

Thu, March 12th, 2015

Yesterday brought another round of sunny, cold and beautiful weather. Temperatures were right around 0F from the parking lot to the ridgetops.

For today, we should have the same sunny skies and cold temperatures. In fact, the Sunburst weather station has just recorded the lowest temperature for this season at 3am, -6F (runner up is -3F on January 25th). There is slight inversion in place with minus single digits in valley bottoms. Temps should rise to the teens at 1,000′ but stay near 0F on the ridgelines. The Northwest winds should remain in the 5-10mph range on the ridgelines today and may pick up a hair later this afternoon into the 15mph range.

Our next shot of snow (and warmer temperatures) is on Sunday and Monday. Until then, enjoy the sunshine!

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

	Temp Avg (F)	Snow (in)	Water (in)	Snow Depth (in)
Center Ridge (1880′)	6	0	0	43
Summit Lake (1400′)	1	0	0	9
Alyeska Mid (1700′)	8	0	0	28

RIDGETOP 24-hour data (6am – 6am)

	Temp Avg (F)	Wind Dir	Wind Avg (mph)	Wind Gust (mph)
Sunburst (3812′)	-2	W	8	18
Seattle Ridge (2400′)	0	n/a	7	23

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.