Fri, December 21, 2012 Turnagain Pass Avalanche Forecast

Fri, December 21st, 2012

Alpine
Above 2,500'

Moderate (2)

Treeline
1,000'-2,500'

Low (1)

Below Treeline
Below 1,000'

Low (1)

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

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

As the Mayan Calendar predicted the end of the world at 2:11 this morning and along with that the end of our meager early season, it seems neither has occurred. The world is still here and so is our shallow snowpack full of persistent weak layers.

The wind slabs that caused so much excitement a week ago have been slowly deteriorating under the cold and clear weather to the point of becoming mostly non-reactive. Snowpack evaluations and the lack of recent avalanches have pointed to a pack that is becoming harder and harder to trigger an avalanche in. However, this is not the case everywhere and we struck gold, as John Fitzgerald stated in his observation, yesterday with finding one of these slopes still flashing red lights.

The areas we are most concerned about are in steeper, unsupported terrain (i.e., above cliffs and on rollovers at the mid-elevations) where stiffer, supportable snow (old wind slabs) are sitting on weak sugary snow. Watching and listening for collapsing and hollow feeling areas will be your best bet at sussing out suspect slopes. If you can punch a pole or boot though the stiff snow, though this may be tough in thicker slabs, and feel unconsolidated snow beneath – steer clear and head for a slope lacking that stiff slab.

Weather

Fri, December 21st, 2012

The SEVERE CLEAR weather conditions will continue to dominate for another couple days. The strong inversion has temperatures at sea level and in the parking lots at Turnagain Pass near -20F. The good news is the temps have jumped to the balmy mid-teens on the ridgetops this morning, where they should remain. Winds have backed to an easterly direction overnight and will pick up to the 10-15mph range, gusting to 30mph, today.

The well entrenched, and not so loved, ridge of high pressure looks to start breaking down near the end of the weekend. Models are hinting at a little precipitation around Monday with a weak low pressure system developing the in Gulf. However, mid-week next week a larger low pressure moving into the Bering will hopefully bring a decent shot of precipitation €“ though this is too far out to say for certain €¦

Happy winter solstice! A little comparison with last year’s solstice: (Turnagain Pass SNOTEL, 1880′)

Dec 21, 2012 Dec 21, 2011
Snow depth 25 € 78 €
Seasonal snowfall 35 € 129 €
Seasonal water 3.4 € 13.4 €

Roughly a quarter of where we were last season at this time €“ oh grim.

This is a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area (this advisory does not apply to highways, railroads, or operating ski areas).

Kevin will issue the next advisory Saturday morning, December 22nd.

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 Sat, September 23rd, 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	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Placer River	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Skookum Drainage	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Turnagain Pass	Closed	Scheduled opening on the Wednesday before Thanksgiving per Chugach National Forest plan. Subject to adequate snow cover.
Twentymile	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Seward District
Carter Lake	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Lost Lake Trail	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Primrose Trail	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Resurrection Pass Trail	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Snug Harbor	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
South Fork Snow River Corridor	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.
Summit Lake	Closed	Scheduled opening per Chugach National Forest plan December 1. Subject to adequate snow cover.