Sat, March 30, 2013 Turnagain Pass Avalanche Forecast

Sat, March 30th, 2013

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

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

Nearly all the activity we’ve seen recently can be classified under wind slab. Fortunately everything we’ve seen has been low volume and isolated to small pockets. The photo below is from 2 days ago on Tincan.

Since we just got a significant additional load of new snow and wind, this concern is worse today. Snowfall was heavy enough yesterday to limit visibility and prevent anybody from getting above treeline. We haven’t seen firsthand the areas of highest concern, but we know it’s been snowing and blowing.

South facing slopes will add another layer of complexity. Multiple layers of buried sun crusts can be found on sunny aspects. We don’t know how those layers will react to the moderate additional snow load, but it’s worth considering that new snow doesn’t bond easily to slippery crusts. Stability aside, those crust layers may affect the quality of skiing and riding on south aspects.

Avalanche Problem 2

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

In areas that were not wind affected we can expect loose snow to sluff easily in steep terrain. Anywhere the wind didn’t stiffen up the surface and slope angles exceed the mid 30 degrees you should expect snow to sluff and entrain volume on the way down. This could be a problem if surprised or in steep channeled terrain.

Weather

Sat, March 30th, 2013

Snow totals for the last 24 hours

Turnagain Pass snotel – 8 inches

Alyeska midway – 10 inches

Summit lake mountains – 6 inches

Wind has been trending from the southeast in Turnagain Pass with variations depending on the location. Temperatures are warmer than they’ve been, producing mixed rain and snow at sea level. Above 1500 feet the snow is dry.

Today’s weather calls for scattered snow showers. The bulk of the precipitation has passed. Expect a slight cooling trend and a diminishing trend with the wind.

Wendy will issue the next advisory tomorrow morning, March 31st.

Observations

Recent Observations for Turnagain Pass

Date	Region	Location	Observer
04/21/21	Turnagain	Observation: Sunburst	Schauer/ Behney Forecaster
04/19/21	Turnagain	Avalanche: Triangle, Seattle creek	Will Morrison
04/18/21	Turnagain	Avalanche: Turnagain Pass Road Obs	Andy Moderow
04/18/21	Turnagain	Observation: Seattle Ridge, approximately 300 yards south of the up track	Brent Byrne
04/17/21	Turnagain	Avalanche: Road obs	Johnston-Bloom / Moderow Forecaster
04/16/21	Turnagain	Avalanche: Seattle Ridge	Wendy Wagner Forecaster
04/16/21	Turnagain	Avalanche: Turnagain Pass, non-motorized side seen from Seattle Ridge	CNFAIC Staff Forecaster
04/16/21	Turnagain	Observation: Sunburst	Lance breeding
04/15/21	Turnagain	Observation: Tincan	Schauer/ Rothman Forecaster
04/13/21	Turnagain	Observation: Turnagain Pass Road Obs	A Schauer Forecaster

Riding Areas

Updated Tue, April 20th, 2021

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	Open	No parking in turnaround at end of the road near the outhouse.
Placer River	Open	Please do not ride along Railroad tracks. Cross tracks at 90 degree angle and clear the right of way.
Skookum Drainage	Closed	The Skookum Valley is closed to snowmachines. This closure occurs annually on April 1 as per the CNF Forest Plan.
Turnagain Pass	Open
Twentymile	Closed
Seward District
Carter Lake	Open
Lost Lake Trail	Open
Primrose Trail	Open
Resurrection Pass Trail	Closed	Closed for the 2020/21 winter season.
Snug Harbor	Open
South Fork Snow River Corridor	Open
Summit Lake	Open