Sun, March 02, 2014 Turnagain Pass Avalanche Forecast

Sun, March 2nd, 2014

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

Wet Loose

Wet Loose

Wet Loose avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.

More info at Avalanche.org

Our unusual winter continues as we enter March in a melt-freeze cycle. A variable, yet mostly supportable, crust covers the snowpack as high as 4,000′ and higher in some areas. With the intense sunshine yesterday, south facing slopes were able to soften – to some degree – and this should be the case again today. No avalanche activity was seen or reported yesterday.

If you are headed out in search of sunshine and softening crusts, keep an eye out for soft snow that becomes several inches deep or more. In this case, wet loose avalanches will be possible to initiate on steep slopes. Though these are fairly slow moving and predictable avalanches, they can have a lot of mass and momentum behind them. Keeping this in mind with your terrain selection will be key. Even a small wet loose avalanche can be dangerous in terrain traps, channeled terrain, cliffs, etc.

Avalanche Problem 2

Cornice

Cornice

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.

More info at Avalanche.org

Cornice falls continue to be a concern with our spring-like temperatures and increasing sunshine. Give cornices a wide berth and steer clear from underneath. They are notorious for breaking further back than expected.

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

At elevations above 2,000′ there is a variable facet/crust combination that sits 1-3′ below the surface. It has been 2-3 days since any slab avalanche activity has been reported at this interface. This activity was in the Placer valley zone and not in the heart of Turnagain Pass. Though the snowpack is tired and the facets are not proving to be very reactive, it is worth noting for those that may be headed out to the far reaches of our advisory area. This is an outlier concern that is mainly confined to >4,000′ in elevation or on steep south slopes that become very soft with the daytime warmth.

Weather

Sun, March 2nd, 2014

It was a beautiful day in the backcountry yesterday with sunny skies and calm winds. During the past 24-hours temperatures have averaged around 32F on the ridgetops and winds have been light and variable. The last precipitation was recorded on February 26/27 where 0.2″ of rain fell up to 4,000′. Side note: The combination of very little wind and intense sun can cause temperature sensors to warm up and record inaccurate readings – this occurred at Sunburst yesterday where a spike of 50F was recorded mid-day even though the true temperature was ~30-35F.

Another round of clear skies is on tap today. Ridgetop winds have shifted overnight to a Northerly direction and will pick up slightly to the 10mph range. Temperatures will remain near 32F on the ridgetops and climb to ~45F at 1,000′.

Monday temperatures will begin to drop as a cold front slides in with a chance for an inch or two of snow on Tuesday into Wednesday.

Webcam junkies:
If you have not done so already – be sure to bookmark this RWIS site for Turnagain Pass. Thanks to the AK DOT who are currently getting the weather station back up and running (not all data is up yet). And a special thanks to Matt Murphy (AK DOT Avalanche Program Director and former CNFAIC forecaster) for programing in views of Eddie’s, Tincan, Seattle Ridge and the new snow stake!

Seattle Ridge (left) and Tincan (right) webcam images from 3/1

Observations

Recent Observations for Turnagain Pass

Date	Region	Location	Observer
05/28/22	Turnagain	Avalanche: Turnagain Pass – late May wet slab cycle	CNFAIC Staff
05/21/22	Turnagain	Avalanche: Magnum, Lipps and Tincan	CNFAIC Staff
05/17/22	Turnagain	Avalanche: Sunburst	CNFAIC Staff
05/17/22	Turnagain	Observation: Tincan Ridge	Joe Kurtak
05/11/22	Turnagain	Avalanche: Cornbiscuit and Magnum west faces	CNFAIC Staff Forecaster
05/07/22	Turnagain	Observation: Granddaddy	Kit Barton
04/29/22	Turnagain	Observation: Sunburst wx station	AS/ MM/ AM/ NH
04/28/22	Turnagain	Observation: More Turnagain Pass/Summit Lake wet slab activity	Alex Marienthal
04/27/22	Turnagain	Observation: Magnum	Sykes / Buttrick Forecaster
04/27/22	Turnagain	Observation: Girdwood/Summit/Turnagain Road obs	A S

Riding Areas

Updated Wed, June 01st, 2022

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 as of May 1 per Forest Plan.
Placer River	Closed	Closed as of April 25th due to insufficient snow coverage.
Skookum Drainage	Closed	Closed as of April 1st per Forest Plan.
Turnagain Pass	Closed	Closed as of June 1st.
Twentymile	Closed	Closed as of April 6th due to insufficient snow coverage.
Seward District
Carter Lake	Closed	Closed as of May 1 per Forest Plan.
Lost Lake Trail	Closed	Closed as of May 1 per Forest Plan.
Primrose Trail	Closed	Closed as of May 1 per Forest Plan.
Resurrection Pass Trail	Closed	Closed as of May 1 per Forest Plan.
Snug Harbor	Closed	Closed as of May 1 per Forest Plan.
South Fork Snow River Corridor	Closed	Closed as of May 1 per Forest Plan.
Summit Lake	Closed	Closed as of May 1 per Forest Plan.