Turnagain Pass RSS

Archives
ARCHIVED - Forecasts expire after 24 hours.
Issued
Thu, January 2nd, 2014 - 7:00AM
Expires
Fri, January 3rd, 2014 - 7:00AM
Forecaster
Kevin Wright
Avalanche risk The Bottom Line

New snow is still the big news for today.  The News Years eve storm produced an active avalanche cycle with natural avalanches during the peak of the wind and precipitation.  We are now on the decreasing trend of that spike in avalanche danger, but caution is still warranted.  

Avalanches were sometimes breaking in the old deeper layers, stripping out to crusts and facets from early season.  Other times they were isolated to the wind-blown storm snow, which was 2+ feet in drifted areas.  

Avalanches that we recorded yesterday – Eddies, Magnum, Cornbiscuit, Seattle ridge, Kern.  Explosive triggers produced slides into the D3 size range.

The challenge today is trying to predict how quickly our snowpack is adjusting and stabilizing to the new load.  Today will be more stable than yesterday, but some problems will be lurking…

A  MODERATE   avalanche danger will be found today, with steeper wind loaded slopes as the primary concern.

Special Announcements

With the new year we want to thank everyone for making the CNFAIC a reality.  We couldn’t do it without the strong support from the community.  

We also want to pass on a reminder to apply for your PFD and consider using Pick. Click. Give. to donate to your local avalanche center.  If you find that this service is valuable to you, please become a member of the nonprofit Friends of the CNFAIC.

Thu, January 2nd, 2014
Alpine
Above 2,500'
2 - Moderate
Avalanche risk
Treeline
1,000'-2,500'
2 - Moderate
Avalanche risk
Below Treeline
Below 1,000'
2 - Moderate
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. Careful snowpack evaluation, cautious route-finding, and conservative decision-making essential. 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

A lot of that storm snow from Dec 31st and Jan 1st came in with substantial wind.  Early in the storm we had several hours of gusts to 90mph or greater on Sunburst.  This means the storm snow is unevenly distributed, and the major problem lies in areas where the snow got drifted rather than scoured by the wind.  

Around Turnagain Pass the predominant wind direction was from the East.  West slopes and crossloaded North and South are the primary concern.  

Storm total amounts – starting Dec 31st

Turnagain Pass – 1.2″ H2O – 12″ snow

Alyeska mid – 1.64″ H2O – 14″ snow

Alyeska top – 2.74″ H2O  

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

When venturing into untracked snow yesterday we noticed a number of collapses (whumphing).  Deep shooting cracks were also evident.  These collapses are almost certainly happening in older weak layers, in the snow that fell in November or December.  The larger avalanches that happened yesterday had the greater volume because they are stripping deeper into the snowpack.  Deeper and more destructive avalanches will be less likely today, but present a greater concern to the backcountry traveler if one is triggered.  

Any collapsing felt today is a significant message and should be telling you to stay off nearby steep slopes.  

Weather
Thu, January 2nd, 2014

The last 24 hours have brought calmer weather.  Precipitation decreased significantly, but at least 3 inches of snow fell in the last 24 hours.  Wind has steadily dropped from strong yesterday to mild this morning.  Temperatures have also consistently decreased by a couple of degrees.

Mostly cloudy skies and snow showers are expected today.  Minimal snow accumulation.  Freezing rain is possible at the road elevation.  Look for light wind and steady temperatures in the 20s.  

Observations
Recent Observations for Turnagain Pass
Date Region Location Observer
05/13/24 Turnagain Observation: Eddie’s, Sunburst, Seattle, Cornbiscuit, Pete’s South H Thamm
05/13/24 Turnagain Observation: Turnagain Pass non-motorized side Amy Holman
05/12/24 Turnagain Observation: Warm up Bowl Tony Naciuk
05/07/24 Turnagain Observation: Turnagain Pass Wet Slabs A S
04/29/24 Turnagain Avalanche: Turnagain aerial obs Tully Hamer
04/27/24 Turnagain Observation: Johnson Pass Noah Mery
04/23/24 Turnagain Observation: Turnagain Sunny Side Travis SMITH
04/21/24 Turnagain Observation: Bertha Creek Anonymous
04/20/24 Turnagain Avalanche: Spokane Creek Schauer/ Mailly Forecaster
04/16/24 Turnagain Observation: Cornbiscuit Krueger / Matthys Forecaster
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.
Become a Member
If you think a public avalanche center is important please support our organization.
Donate Now
Become a Sponsor
Supporting the CNFAIC proudly shows that your business or organization values the safety of our snow sports community.
Become a Sponsor