Avalanche Advisory for Wednesday, December 26th 2012

Expires 12:00 midnight December 26, 2012

Tuckerman and Huntington Ravines have Moderate avalanche danger today.  Natural avalanches are unlikely and human triggered avalanches are possible.  We have not begun forecasting for the Lobster Claw, Right Gully, the Lower Snowfields, or Little Headwall in Tuckerman and the Escape Hatch in Huntington due to a general lack of snow in these areas.  Forecasting will begin for these areas when conditions warrant although avalanche activity may occur before this point.

This is the first 5 Scale U.S. Danger Rating Advisory of the season. Snow conditions have changed rapidly over the past week and clear skies are finally giving us the first view of the mountain we have had in quite a while.  The summit has received 42.2” (107cm) of snow over the past 10 days bringing us back to the normal range for the month.  Of this, 6.9” (17.5cm) fell yesterday with a low water content of 5% which was easily moved around in a number of gullies.  This has given us some concerns for touchy low density slabs peppered across both Ravines.  The rating of Moderate reflects this issue, but it is not a widespread concern or found in slabs of appreciable size. Because of this we are barely in the definition of Moderate and the savvy traveler with avalanche skills shouldn’t have trouble analyzing the terrain for a reasonable route.  The low density snow from yesterday will likely be the weak layer for the expected storm bearing down upon us from the south.  We will be in a WINTER STORM WARNING beginning tonight and stretching all the way until Friday morning.  Heavy snow will begin during the overnight and through tomorrow. The heaviest periods will be during daylight hours on Thursday accumulating in the neighborhood of 12” (30cm) or more. This will be brought in on building winds from the SE and the E.  These wind directions won’t cause the level of hazard that a westerly event does, but we should see a significant cross loading problems in our N and S facing gullies. Anticipate an elevated avalanche danger during the storm and potentially afterwards on Friday as wrapping winds should shift to our prevailing NW. This will cause new problems.  So….. here we go, winter is fully hunkering in and you’ll be hearing from us every day with a 5 scale danger rating forecast.  Hope you had a great holiday and we’ll talk to you tomorrow.

 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 8:33a.m. A new advisory will be issued tomorrow.

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

12-26-2012 Print Friendly