Turnagain Pass RSS

Archives
ARCHIVED - Forecasts expire after 24 hours.
Issued
Thu, December 15th, 2016 - 7:00AM
Expires
Fri, December 16th, 2016 - 7:00AM
Forecaster
Heather Thamm
Avalanche risk The Bottom Line

A LOW  avalanche danger remains in the mountains surrounding Turnagain Pass where triggering loose surface snow could be fast moving, enough to knock you off your feet in steep terrain. Popping out an old wind slab sitting on faceted snow, breaking off a chunk of cornice or triggering a larger €˜outlier’ avalanche are all in the realm of ‘unlikely possibilities’ but worth noting.  

*Today pay attention for changing weather conditions and always practice good travel habits; expose one person at a time, watch your partners, have an escape route planned and group up in safe zones.  

 

Special Announcements

TONIGHT: Fireside Chat: Avalanche Awareness and Rescue  with the CNFAIC in Girdwood at the  Powder Hound Ski Shop! December 15 @ 6:30 pm – 8:00 pm. FREE!

Thu, December 15th, 2016
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. 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
  • Announcement
    Announcement

If you are headed to steep slopes, pay attention for ‘facet’ sluff (yesterday we received a report that loose surface snow was becoming fast moving and more difficult to manage than previous days.) Also watch out for cornices and old wind slabs near ridges – all of these avalanche concerns are too small to bury a person, but could take you for a ride in an undesirable place. Lastly, be aware of an ‘outlier’ slab avalanche that could fail mid-pack due to the Nov 16 buried surface hoar, especially in areas that haven’t seen much traffic.

Light snowfall is expected to start this afternoon with the possibility of 1-4 inches falling this evening. This is not quite enough precip or the right timing to elevate the danger rating for today. As always be prepared to change your plans should snowfall arrive early and intensity increase beyond what is forecasted. 

As we anxiously await a change in the weather we have been taking inventory of the surface conditions and snowpack structure in our region. It has been just over two weeks since our last snow event left 6-10”, and cold and clear weather has dominated our region. This has been the perfect recipe for creating weak, poorly bonded snow: near surface facets and surface hoar, as well as depth hoar in shallow/thin areas of the snowpack. With a few inches of snow expected tonight and heavier amounts forecasted into the weekend we will see just what the avalanche conditions will do. Should we get significant precipitation be prepared for dangerous avalanche conditions this weekend and into next week. 

 

An observer sent in this photo yesterday of the Eastern facing slopes of Seattle Ridge, with a great question, “Does this count as skier compaction?” Well… don’t get excited yet. It’s too soon to tell if the weak surface snow (one of several future weak layers) was disturbed enough in this high traffic area to truly be considered compaction. AND we mustn’t forget about the November 16 surface hoar that is still buried 1-2’ below the surface in some areas. For more discussion on the topic of ‘skier compaction’ check out the observation HERE. Photo by Andy Milauskas

 

Weather
Thu, December 15th, 2016

Yesterday an inversion persisted with temperatures averaging in the low 20F’s the alpine and single digits (F) near sea level. Skies were mostly clear with valley fog at lower elevations. Ridge top winds were calm and no new precipitation was recorded. Conditions were similar overnight.

Expect partly cloudy skies to become overcast in the afternoon and light precipitation to start falling mid-day. Light winds will shift from the South becoming Easterly and increasing to moderate by this evening. Temperatures are expected to increase into the high 20F’s and 1-4 € of snow could fall by this evening.

This is the first major pattern shift in weeks and several low pressure systems are on track to impact Southcentral, Alaska. Right now Saturday and Sunday look to be the more precipitous events for Western Prince William Sound. There is some uncertainty about how warm these next few storms will be, but rain was mentioned near the coast and inland at times over over weekend in the NWS  forecast discussion.  

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

  Temp Avg (F) Snow (in) Water (in) Snow Depth (in)
Center Ridge (1880′) 21   0   0   20
Summit Lake (1400′) 13   0   0   5  
Alyeska Mid (1700′) 20    0 0   9  

RIDGETOP 24-hour data (6am – 6am)

  Temp Avg (F) Wind Dir Wind Avg (mph) Wind Gust (mph)
Sunburst (3812′) 23   variable   2   8  
Seattle Ridge (2400′) 22   variable   3   11  
Observations
Recent Observations for Turnagain Pass
Date Region Location
05/13/24 Turnagain Observation: Eddie’s, Sunburst, Seattle, Cornbiscuit, Pete’s South
05/13/24 Turnagain Observation: Turnagain Pass non-motorized side
05/12/24 Turnagain Observation: Warm up Bowl
05/07/24 Turnagain Observation: Turnagain Pass Wet Slabs
04/29/24 Turnagain Avalanche: Turnagain aerial obs
04/27/24 Turnagain Observation: Johnson Pass
04/23/24 Turnagain Observation: Turnagain Sunny Side
04/21/24 Turnagain Observation: Bertha Creek
04/20/24 Turnagain Avalanche: Spokane Creek
04/16/24 Turnagain Observation: Cornbiscuit
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.