Mon, January 06, 2014 Turnagain Pass Avalanche Forecast

Mon, January 6th, 2014

Alpine
Above 2,500'

Considerable (3)

Treeline
1,000'-2,500'

Considerable (3)

Below Treeline
Below 1,000'

Considerable (3)

Alpine Above 2,500'		Considerable (3)
Treeline 1,000'-2,500'		Considerable (3)
Below Treeline Below 1,000'		Considerable (3)

Danger Scale:

No Rating (0)

Low (1)

Moderate (2)

Considerable (3)

High (4)

Extreme (5)

Avalanche Problem 1

Persistent Slabs

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

More info at Avalanche.org

The snowpack received a serious shock over the weekend. Over a foot of new snow fell in a short period of time on Saturday night Jan. 4th. This resulted in widespread natural avalanching throughout the forecast area. High winds have eroded the snow near many of the areas that have avalanched, making it hard to see this evidence. Yesterday we were able to see this evidence but it was not blatantly obvious.

What we do know is that the snowpack still has a weak foundation. Time will allow the snowpack to adjust to this newest load to some degree. However, it has been only one day since we have had significant natural avalanche activity. The snowpack simply needs more time to adjust. The consequences of triggering an avalanche right now are potentially severe.

Dense slabs ranging between 1-3 feet deep are laying in wait for the right trigger. This may come in the form of a large group, or it may just take one person to hit a thin spot in the slab. Now is an important time to recognize and avoid likely trigger points. Areas of shallow snow, convexities and steep slopes should be avoided today.

Below is an image of one of many large natural avalanches that occured over the weekend.

Todd's

Avalanche Problem 2

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

New snow, warm temperatures and moderate wind (out of the East) will make it possible for humans to trigger shallow new wind slabs in steep terrain. These slabs on their own will not be large. However, triggering one of these newly formed slabs will have the potential to trigger deeper weak layers in the snowpack. It will be important to avoid steep slopes especially in areas receiving 6 or more inches of new snow and wind today.

Weather

Mon, January 6th, 2014

In the past 24 hours a trace of new snow has fallen on Turnagain Pass. Girdwood valley has picked up another 3-5 € of snow. Temperatures climbed overnight with ridge top stations in the high 20s F with the Turnagain Pass SNOTEL (1,880′) showing an overnight high of 36 F. Winds at the Sunburst station have been light to moderate out of the East averaging 18 mph.

Today expect cloudy skies and snow showers mainly in the first half of the day. Snow accumulation of 4-6 € are possible. Ridgetop winds will be out of the East at 25-30 mph. Temperatures will remain mild, in the low to mid 30s F at 1,000′.

The weather pattern to our South and West is complex. Computer models are doing a poor job of projecting weather beyond today. Expect unsettled weather over the next several days with modest precip amounts and generally mild temperatures.

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.