Tue, January 06, 2015 Turnagain Pass Avalanche Forecast

Tue, January 6th, 2015

Alpine
Above 2,500'

Moderate (2)

Treeline
1,000'-2,500'

Low (1)

Below Treeline
Below 1,000'

No Rating (0)

Alpine Above 2,500'		Moderate (2)
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

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

We have moved into a time period where buried weak layers have become very difficult to trigger. Time and settling of the snowpack has allowed layers of buried surface hoar and facets (1-3 feet deep) to adjust and become less reactive.

The makeup, or structure of the snowpack is such that should an avalanche occur there is still potential for entire slopes to release. Testing of these layers over the past few weeks has shown this potential.

Slabs that built up on top of these layers have become very strong. These slabs can withstand a lot of weight and force. This is another contributing factor to the low likelihood of triggering an avalanche.

Areas where you could trigger an avalanche today include slopes over 40 degrees, convexities and slopes with a shallow snowpack. The Girdwood Valley and Summit Lake areas have, in general thinner snowpacks than Turnagain Pass. Thin spots can still be found throughout the forecast area and are worth avoiding. Given the current hardness of slabs it is important to keep in mind that slabs can break above you and be very difficult to ride or ski off.

If venturing onto steep terrain practice good travel habits:
Expose only one person at a time
Utilize islands of safety for spotting and re-grouping
Identify escape routes in the event of a slab releasing
Communicate route decisions and plans within your group effectively
Be aware of groups above and below you and avoid exposing those groups to avalanche hazard

Weather

Tue, January 6th, 2015

Yesterday was another day of clear and calm conditions. No new precipitation fell. Winds were light coming out of the Eastern half of the compass. Temperatures were on the cold side, with ridgetops in the teens-20’s F and some valley locations remaining in the single digits F under an inversion.

Today will be more of the same. Temperatures at ridegtops will be in the 20s F and some valleys will remain in the single digits. Winds will be light out of the East at 5-10mph.

The ridge of high pressure that is currently parked over much of mainland Alaska looks to begin breaking down by Wednesday night. Clouds, warming temps and precipitation will move in as we near the weekend.

*Sunburst data is 3pm-6am due to temporary station malfunction

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

	Temp Avg (F)	Snow (in)	Water (in)	Snow Depth (in)
Center Ridge (1880′)	21	0	0	33
Summit Lake (1400′)	3	0	0	6
Alyeska Mid (1700′)	21	0	0	25

RIDGETOP 24-hour data (6am – 6am)

	Temp Avg (F)	Wind Dir	Wind Avg (mph)	Wind Gust (mph)
Sunburst (3812′)	22	ESE	4	11
Seattle Ridge (2400′)	19	E	9	20

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 Mon, May 15th, 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	Open	Chugach NF staff will be assessing daily after May 15th. Please keep machines on the snow and avoid brown spots to keep this area open as long as possible.
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.