Turnagain Pass Avalanche Forecast RSS

Archives
ARCHIVED FORECAST - All forecasts expire after 24 hours from the posting date/time.
Issued
Sat, February 15th, 2014 - 7:00AM
Expires
Sun, February 16th, 2014 - 7:00AM
Forecaster
John Fitzgerald
Avalanche risk The Bottom Line

The avalanche hazard is CONSIDERABLE today for all terrain above treeline.   Dangerous conditions exist.   Wind slabs up to 2 feet in depth as well as loose snow avalanches are likely to be triggered by humans venturing above treeline.   Natural avalanches are also possible in the higher elevations today.

Below treeline the hazard is MODERATE, where it will be possible for humans to trigger loose snow and soft slab avalanches up to 18″ in depth on all aspects.  

Knowledge of terrain above will also be critical today, as avalanches in the higher elevations have the potential to run into lower elevation areas.

Special Announcements

New snow over the past week is helping to rebuild the snowpack in areas that were showing bare ground after the January rain and warmth.   Motorized areas on the Chugach National Forest remain closed to avoid resource damage.   The good news is that we are getting closer to re opening these areas.   Check the bottom of the page for the latest updates as well as the Chugach National Forest website.

————————————————————————————————————————————————————————-

There are still a few raffle tickets left for the February 21st drawing to win some great prizes including a day of Valdez Heli Skiing or Alaska Airlines Tickets!  Join the Friends of CNFAIC at The Midnight Sun Brewery  from 6-8PM Sunday night to pick up your raffle ticket and some free swag!

Thanks to our sponsors!
Sat, February 15th, 2014
Alpine
Above 2,500'
Considerable (3)
Avalanche risk
Treeline
1,000'-2,500'
Moderate (2)
Avalanche risk
Below Treeline
Below 1,000'
Moderate (2)
Avalanche risk
Alpine
Above 2,500'
Avalanche risk
Considerable (3)
Treeline
1,000'-2,500'
Avalanche risk
Moderate (2)
Below Treeline
Below 1,000'
Avalanche risk
Moderate (2)
Danger Scale:
No Rating (0)
Low (1)
Moderate (2)
Considerable (3)
High (4)
Extreme (5)
Avalanche Problem 1
  • Storm Slabs
    Storm Slabs
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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

Snowfall amounts over the past 24 hours ranging from 6” in the lower elevations to 18” in the higher elevations are bringing with it all of the issues related to storm snow.

Loose Snow avalanches
Yesterday my partner and I were able to easily produce sluffing in steep terrain, generally over 40 degrees.  Loose snow sluffs will be easy to trigger today and could entrain enough snow to knock people off of their feet.  This issue becomes exacerbated when traveling above terrain traps such as cliffs, trees, and gullies.

Storm Slabs
Enough snow has fallen over the past 24 hours to create slabs without the presence of wind.  While the general set up on the surface is loose snow, slabs were beginning to form in sheltered areas late in the day yesterday.  Be on the lookout for shooting cracks when traveling on terrain 35 degrees and above today.  While these slabs are generally soft, the potential exists for them to propagate across slopes and run far.

Wind slabs
Winds out of the East cranked up enough yesterday afternoon and into the night to create wind slabs up to 2 feet in depth that will be very sensitive to the weight of a person today.  Avoiding leeward slopes above 35 degrees is your best bet for avoiding this problem.  These newly formed slabs also have the potential to trigger deeper layers in the snowpack.

Avalanche Problem 2
  • Persistent Slabs
    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

The most prominent weak layer above 3,500’ is facets sitting on the stout January crust.  This layer (along with the crust) has been associated with remotely triggered avalanches over the last week.  Since Feb 7th, up to 30” of snow with 2” of water has fallen in the higher elevations.  This slab has had time to settle and become more dense.  The interface between this slab and the January crust is suspect.  Visibility yesterday limited our ability to assess this interface.  Because of this lack of information, this layer & the slab above it are guilty until proven innocent.  Avoidance of steep (over 35 degree) upper elevation starting zones and cross loaded gullies will be the best management tactic related to this problem today.

Weather
Sat, February 15th, 2014

Winter Part 2 has arrived!

In the past 24 hours the Turnagain Pass SNOTEL site has picked up 14 € of new snow with 1 € of water.   The Girdwood Valley has seen less amounts, with stations averaging 6-8 € snow with .5 € of water.   Winds that picked up overnight have calmed this morning.   Sunburst averaged 20mph with gust to 69mph.   Ridge top temps have averaged in the low teens and are currently reading in the high single digits F.

Today expect a continuation of light snowfall.   Accumulations of 2-4 € are possible.   Temperatures at 1,000′ will be in the teens to low 20s F.   Winds will be out of the East at 10-15 mph.

A very large area of Low pressure centered over Kodiak island will remain in place through the weekend.   Expect light snow with occasional breaks in the clouds to continue through the next several days.

Observations
Recent Observations for Turnagain Pass
Date Region Location
05/28/22 Turnagain Avalanche: Turnagain Pass – late May wet slab cycle
05/21/22 Turnagain Avalanche: Magnum, Lipps and Tincan
05/17/22 Turnagain Avalanche: Sunburst
05/17/22 Turnagain Observation: Tincan Ridge
05/11/22 Turnagain Avalanche: Cornbiscuit and Magnum west faces
05/07/22 Turnagain Observation: Granddaddy
04/29/22 Turnagain Observation: Sunburst wx station
04/28/22 Turnagain Observation: More Turnagain Pass/Summit Lake wet slab activity
04/27/22 Turnagain Observation: Magnum
04/27/22 Turnagain Observation: Girdwood/Summit/Turnagain Road obs
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.

Subscribe to Turnagain Pass
Avalanche Forecast by Email

This is a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area. This advisory does not apply to highways, railroads or operating ski areas.