Mon, April 11, 2016 Turnagain Pass Avalanche Forecast

Mon, April 11th, 2016

Alpine
Above 2,500'

Moderate (2)

Treeline
1,000'-2,500'

Considerable (3)

Below Treeline
Below 1,000'

No Rating (0)

Alpine Above 2,500'		Moderate (2)
Treeline 1,000'-2,500'		Considerable (3)
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

Announcement

Announcement

More info at Avalanche.org

After driving through Turnagain Pass yesterday and observing the state of Seattle Ridge and the uptrack, travel in avalanche terrain (including runout zones) on the motorized (West Side) is not recommended. The snowpack below 2500′ is saturated; there is natural wet loose activity and a very active glide avalanche cycle going on. Unfortunately there really isn’t a way to negotiate a route to the ridge without being in danger. Seattle Ridge is literally falling apart. Essentially the hazard is HIGH on this side of the pass. Until we get a very hard freeze, the glide avalanche cycle completely ends or all the snow in the starting zones that threaten the uptrack avalanches, traveling here is like playing Russian Roulette.

Glide avalanche hazard also exists on the non-motorized slide. Travel underneath existing glide cracks is not recommended. In addition, be on the lookout for new glide cracks forming.

Avalanche Problem 2

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

Natural wet loose avalanche activity was observed yesterday and may continue today. Overnight there has been a slight cooling trend with mid elevation temperatures dipping below freezing. This may cause a superficial freeze and thin crust. However if the sun comes out, more rain falls or the temperatures climb, human triggered wet loose avalanches will continue to be likely in steep terrain below 2500′ and natural wet loose avalanches will be possible.

If the snow feels punchy, unsupportable or slushy and you find yourself sinking in on your skis or snowmachine it is time to get off the slope.

Additional Concern

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

In the Alpine new snow and wind have likely formed wind slabs on steep leeward slopes. Yesterday there was evidence of blowing snow and wind effect. The fresh wind slabs may be quite tender along ridgelines and on unsupported terrain. There is potential for a little more snow today and easterly winds. Look for cracking and remember warm temperatures and sun can make these slabs even more touchy.

Cornices: This hazard continues to loom along ridgelines in the Alpine and may be triggered by the weight of a skier or a snowmachiner. These may also fall naturally with additional snow/wind loading or rapid warming. Remember these break farther back than expected and travel on or underneath should be avoided.

Wind plumes on Sunburst yesterday. photo: Joe Kurtak

Weather

Mon, April 11th, 2016

Yesterday was mostly cloudy to partly sunny with rain/snow showers and gusty easterly winds. Temperatures were in the mid 20Fs to mid 40Fs depending on elevation.

Today will be mostly to partly cloudy with rain/snow showers and a possibility of sun. Temperatures will be in the mid 20Fs to low 40Fs. Winds will be easterly 10-25 mph.

For Tuesday there looks to be a break in the showery weather with clearing skies as a ridge of high pressure moves over the region. There is another low moving into the Gulf that will most likely put us back into the moist pattern of scattered showers later in the week.

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

	Temp Avg (F)	Snow (in)	Water (in)	Snow Depth (in)
Center Ridge (1880′)	35	0	0*	114
Summit Lake (1400′)	37	0	0	32
Alyeska Mid (1700′)	34	0	.5	100

*Center Ridge maybe under reporting, data has been wonky for the past two weeks

RIDGETOP 24-hour data (6am – 6am)

	Temp Avg (F)	Wind Dir	Wind Avg (mph)	Wind Gust (mph)
Sunburst (3812′)	26	ENE	18	51
Seattle Ridge (2400′)	29	SE	20*	38

*Seattle Ridge did not record winds from 5 am-10 am yesterday.

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.