Fri, December 04, 2015 Turnagain Pass Avalanche Forecast

Fri, December 4th, 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

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

For almost a week now intermittent snow showers have added a welcome 8-12″ of low density snow at the mid-mountain elevations. Another round last night added 2-3″ of this. Snow quality continues to be reported as “excellent” – especially above treeline where “dust-on-crust” conditions disappear. Winds have been light over the past few days and are expected to be light again today, however, with such loose snow available for transport, keep in mind it can be blown into slabs easily. Otherwise, watch for sluffing on steep slopes.

Additional Concern

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

How is the ‘snowpack structure’ looking as a whole? In general, pretty good. However, we are tracking a layer of old faceted snow that sits near the ground. This layer is likely responsible for some very sizeable natural avalanches during the Thanksgiving weekend storm, yet signs point to the layer adjusting since then and becoming unreactive. Until we gather enough data to rule this potential weak layer out, it’s something to keep in mind.

Weather

Fri, December 4th, 2015

Generally mild weather has been over us for the past 6 days. We have seen light Easterly winds, isolated snow showers and temperatures in the mid 20’s F on the ridgetops and near freezing at sea level.

Overnight, a quick moving disturbance added roughly 2-3″ of light snow at Turnagain Pass and Summit Lake while Girdwood Valley looks to have seen around 4″. Winds are light and variable currently and slated to turn back Easterly in the 5-10mph range today. Skies should be partly cloudy this morning before filling back in later today with a chance for another 1-2″ of low density snow this evening. Temperatures have dropped to the lower 20’s F on the ridgetops where they should remain today.

This weekend looks to be nice with partly cloudy skies, temperatures in the 20’s F and light winds. Stay tuned.

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

	Temp Avg (F)	Snow (in)	Water (in)	Snow Depth (in)
Center Ridge (1880′)	26	2	0.2	25
Summit Lake (1400′)	24	2	0.2	12
Alyeska Mid (1700′)	27	3.5	0.25	20

RIDGETOP 24-hour data (6am – 6am)

	Temp Avg (F)	Wind Dir	Wind Avg (mph)	Wind Gust (mph)
Sunburst (3812′)	22	NE	5	16
Seattle Ridge (2400′)	24	N/A	N/A	N/A

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.