Thu, January 02, 2014 Turnagain Pass Avalanche Forecast

Thu, January 2nd, 2014

Alpine
Above 2,500'

Moderate (2)

Treeline
1,000'-2,500'

Moderate (2)

Below Treeline
Below 1,000'

Moderate (2)

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

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

A lot of that storm snow from Dec 31st and Jan 1st came in with substantial wind. Early in the storm we had several hours of gusts to 90mph or greater on Sunburst. This means the storm snow is unevenly distributed, and the major problem lies in areas where the snow got drifted rather than scoured by the wind.

Around Turnagain Pass the predominant wind direction was from the East. West slopes and crossloaded North and South are the primary concern.

Storm total amounts – starting Dec 31st

Turnagain Pass – 1.2″ H2O – 12″ snow

Alyeska mid – 1.64″ H2O – 14″ snow

Alyeska top – 2.74″ H2O

Avalanche Problem 2

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

When venturing into untracked snow yesterday we noticed a number of collapses (whumphing). Deep shooting cracks were also evident. These collapses are almost certainly happening in older weak layers, in the snow that fell in November or December. The larger avalanches that happened yesterday had the greater volume because they are stripping deeper into the snowpack. Deeper and more destructive avalanches will be less likely today, but present a greater concern to the backcountry traveler if one is triggered.

Any collapsing felt today is a significant message and should be telling you to stay off nearby steep slopes.

Weather

Thu, January 2nd, 2014

The last 24 hours have brought calmer weather. Precipitation decreased significantly, but at least 3 inches of snow fell in the last 24 hours. Wind has steadily dropped from strong yesterday to mild this morning. Temperatures have also consistently decreased by a couple of degrees.

Mostly cloudy skies and snow showers are expected today. Minimal snow accumulation. Freezing rain is possible at the road elevation. Look for light wind and steady temperatures in the 20s.

Observations

Recent Observations for Turnagain Pass

Date	Region	Location	Observer
05/06/20	Turnagain	Avalanche: Pastoral Peak, north face	Andy Duenow
04/10/20	Turnagain	Avalanche: Wolverine	Mike Records
04/10/20	Turnagain	Observation: Eddies lookers right shoulder	Matt Yoder
04/09/20	Turnagain	Observation: Bench Peak	Mike Records
04/04/20	Turnagain	Observation: Tincan	Anonymous
04/04/20	Turnagain	Observation: Pete’s North	Anonymous
03/26/20	Turnagain	Avalanche: Tincan – Proper (SW facing)	CNFAIC Staff
03/26/20	Turnagain	Avalanche: Seattle Ridge	W Wagner Forecaster
03/25/20	Turnagain	Avalanche: Sunburst Uptrack @ 2000′	J. Boisvert
03/24/20	Turnagain	Observation: Turnagain – Road Observations	W Wagner Forecaster

Riding Areas

Updated Mon, October 26th, 2020

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
Placer River	Closed
Skookum Drainage	Closed
Turnagain Pass	Closed
Twentymile	Closed
Seward District
Carter Lake	Closed
Lost Lake Trail	Closed
Primrose Trail	Closed
Resurrection Pass Trail	Closed
Snug Harbor	Closed
South Fork Snow River Corridor	Closed
Summit Lake	Closed