General Avalanche Advisory, Wednesday, 12-11-2013

Expires at 12:00 midnight Friday 12-13-2013.

This is an early season General Advisory for Tuckerman and Huntington Ravines.

General Advisories are issued when isolated instabilities may exist within the forecast areas. Forecasts using the 5-scale danger rating system will begin when snowfields and bed surfaces become more developed. Please remember that avalanche activity may occur before the issuance of a 5-scale danger rating forecast. As always, you need to make your own snow stability assessments when traveling in avalanche terrain.

Potential instability problems are currently limited to isolated snowfields in each ravine. Unstable snow can develop in any location where new snow can be loaded onto a potential bed surface. The largest of these bed surfaces can currently be found in Left Gully, the Chute, and the Lip area of Tuckerman and Central, Pinnacle and Odell Gullies in Huntington. Smaller but equally hazardous snowfields can also be found on benches that allow sluffing snow to accumulate. Spatial variability predominates in the early season so climbers should approach low angle ice between steeper bits on any ice climb or mountaineering route with caution.  These lower angle sections contain the deepest snow on what may be the slickest bed surface. Our thin snowpack is obscuring rocks and boilerplate water ice which will create a significant hazard to hikers and climbers until we get more snow. Micro-spikes and crampons as well as the patience to stop and put them on or switch between the two will go a long way towards preventing a potentially disastrous lower leg injury in the upcoming frigid weather. The Lion Head Summer Route is still open but has several sections of steep ice that are difficult to negotiate with anything less than crampons.

Thursday, December 5 was a warm rainy day on the mountain, which brought about a half inch of rain.  Since then, cold temperatures have prevailed with the summit recording 7” of snow Monday and Tuesday, December 9th and 10th. Field work in Tuckerman Ravine revealed generally good bonding of the new snow on the old rain crust.  Mid storm layers form the weaker interface with smoother Q2 shears. New snow on ice was reactive.

Check www.mountwashingtonavalanchecenter.org frequently as we move through December for the latest avalanche advisory before heading into avalanche terrain. We’re excited to be back at it and look forward to seeing you in the mountains!

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
  • Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast.
  • For more information contact the Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or the Harvard Cabin.
  • Posted 7:54a.m., Wednesday, December 11, 2013. 

 

Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856

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