Turnagain Pass RSS

Archives
ARCHIVED - Forecasts expire after 24 hours.
Issued
Tue, April 8th, 2014 - 7:00AM
Expires
Wed, April 9th, 2014 - 7:00AM
Forecaster
Wendy Wagner
Avalanche risk The Bottom Line

Most areas today will continue to have a LOW avalanche danger as only a few inches of snow is expected to blanket the mountains. However, in favored locations that see 6″ or more with gusty winds the danger will rise to MODERATE. In this case, fresh wind slabs ~8″ thick may be found on leeward slopes near ridgelines and on steep rollovers. Additionally, watch for shallow new snow sluffs and, if the sun pokes through later in the day, natural wet sluffs from rocks and trees.

Tue, April 8th, 2014
Alpine
Above 2,500'
1 - Low
Avalanche risk
Treeline
1,000'-2,500'
1 - Low
Avalanche risk
Below Treeline
Below 1,000'
1 - Low
Avalanche risk
0 - No Rating
1 - Low
2 - Moderate
3 - Considerable
4 - High
5 - Extreme
Avalanche risk Avalanche risk Avalanche risk Avalanche risk Avalanche risk
Travel Advice Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern. Dangerous avalanche conditions. Dangerous avalanche conditions. Very dangerous avalanche conditions. Travel in avalanche terrain not recommended. Extraordinarily dangerous avalanche conditions. Avoid all avalanche terrain.
Likelihood of Avalanches Natural and human-triggered avalanches unlikely. Natural avalanches unlikely; human-triggered avalanches possible. Natural avalanches possible; human-triggered avalanches likely. Natural avalanches likely; human-triggered avalanches very likely. Natural and human-triggered avalanches certain.
Avalanche Size and Distribution Small avalanches in isolated areas or extreme terrain. Small avalanches in specific areas; or large avalanches in isolated areas. Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas. Large avalanches in many areas; or very large avalanches in specific areas. Very large avalanches in many areas.
Avalanche Problem 1
  • Wind Slabs
    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

For the first time in just over 3 weeks we have measureable snow to report! However, accumulations are scant – but still accumulations nonetheless. So far we have picked up roughly 3″ in Turnagain Pass and Girdwood Valley with another 1-3″ possible today. Colder air is moving in and the new snow is low in denisty and reaching sea level.

Winds are forecast to be generally light, but on some ridge tops may be just strong enough to move the light snow around and form shallow wind slabs on leeward slopes. With such low snow amounts these are not likely to pose much threat unless you find yourself in a zone with 6″ or so of new snow. In this case, quick hand pits, watching for wind drifted snow and any cracking or ‘slabing’ up of the new snow will be key in sussing out wind slabs. Watch for them to be touchy and not bonding well with the crusty conditions underneath. 

For a sense of the expected surface conditions (ah, ‘dust-on-crust’) – below are shots of yesterday’s snow cover that is now mostly frozen with 1-3+?” of light snow on top:

Seattle Ridge – snowmachine ‘up-track’              NW ridge and face of Magnum                          SW terrain on Tincan
  

Avalanche Problem 2
  • Dry Loose
    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

On slopes lucky enough to receive over a few inches of snow you’ll likely find it easy to initiate predictable and low volume dry sluffs.

**Later in the day, if the sun is able to warm the new snow watch for roller-balling from rocks/trees/alders/etc. If the sun is intense enough, these could turn into decent size wet snow sluffs and something to be aware of if you are in confined terrain such as gullies. Damp/wet snow sluffs can push a person around much more than the dry variety that should be present earlier in the day.

 

 

Weather
Tue, April 8th, 2014

Yesterday’s partly cloudy skies, light winds and warm temperatures (30-40deg F) continued to melt out the existing snow cover. Overnight however, cloud cover moved back in and snow began to fall as cold air slides in from the Northwest and collides with a warm and weak low pressure to our South – finally a little re-fresher!

Snowfall estimates as of 6am this morning are below.  The go-to Turnagain Pass and Summit SNOTEL sites are not reporting this morning so estimates are a bit rough. But, you can watch the lighted snow stake loop on the RWIS Turnagain Pass site for an idea.

Turnagain Pass:  3″
Summit Lake:  0″
Girdwood Valley:  3-4″

It looks like we should get another 1-3″ of very low density snow on top of this throughout the day along with patches of sunshine. Temperatures should continue to drop to around 10F on the ridge tops and to the low 20’sF at 1,000′ – snow to sea level. Winds will remain mostly light to moderate (10-15mph) and switch from the Northwest to a Northeast direction with gusts to 20mph.

Beginning tonight, a return to clear skies and mild weather is in store as another high pressure builds and extends through the remainder of the week.

Observations
Recent Observations for Turnagain Pass
Date Region Location
11/16/23 Turnagain Observation: Tincan Common
11/14/23 Turnagain Observation: Sunburst/Magnum
11/14/23 Turnagain Observation: Seattle Ridge
11/13/23 Turnagain Avalanche: Tincan Trees
11/12/23 Turnagain Observation: Sunburst
11/12/23 Turnagain Avalanche: Goldpan – avalanche
11/11/23 Turnagain Observation: Tincan Common
11/11/23 Turnagain Observation: Taylor Pass – Sunburst
11/10/23 Turnagain Observation: Tincan
11/10/23 Turnagain Observation: Tincan Trees
Riding Areas

The riding areas page has moved. Please click here & update your bookmarks.

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.