Avalanche Advisory for Tuckerman and Huntington Ravines

Printable Advisory

Posted: 8:15, Wednesday, December 15, 2010
This is an early season GENERAL AVALANCHE ADVISORY.  Use of the 5-scale danger rating system will begin when conditions warrant.  A General Advisory is issued when instabilities are isolated within the entire forecast area. However, it is important to realize that avalanche activity may occur within these locations before the issuance of a 5-scale forecast. Under a General Advisory you need to make your own snow stability assessments when venturing into avalanche terrain.

Despite a recent soaking, winter weather is the dominant force in the mountains and anyone planning to be up here in the next few days needs to be prepared for cold weather and the potential for unstable snow in the Ravines.  NW winds have brought very cold air to the mountains and the associated upslope flow will provide reasonable hope for accumulating snow between Wednesday and Thursday.  Since last Sunday, the mountain has recorded around 4” (102 mm) of water with at least half of that falling as rain.  The rest was a mixed bag of precipitation with enough snow to allow the mountain to progress further into its winter form than it was before Sunday.  As of Wednesday morning there was 15.5” (40 cm) of snow at the Hermit Lake snow plot.  A brief moment of clearing provided me with views of Tuckerman on Tuesday and I observed that conditions have progressed and we are getting close to switching to a 5-scale advisory.  The areas that have the most well developed avalanche paths right now are Left Gully and the Chute in Tuckerman Ravine and Central Gully in Huntington.  Snowfields through the Headwall and the Lip in Tuckerman continue to grow as well.  On the flip side, a number of our forecast areas have very little snow in them right now.  It is important for you to realize that unstable snow may exist in the Ravines and avalanche activity can occur.  Be on the lookout for new wind slabs that form as new snow accumulates and moderate to light NW winds transport it into the Ravines over the next few days.  We are monitoring conditions closely and will keep you updated as conditions change. 

Cold temperatures coupled with a lot of surface water from the recent rain are working together to make a lot of ice.  This is good news if you are an ice climber but remember that recent weather damaged existing ice and ice dams may be forming in a number of areas.  All of the recent mood swings the mountain has been through should make you skeptical about the overall condition of ice for a little while.  Throw some rock gear on your rack and expect some of these issues along the way.  It should be no surprise to you that mountaineering skills and equipment are needed to travel in the mountains right now.  Along with cold winter weather, I suspect there will be a lot of water ice developing on the trails over the next few days that will add to your adventure. 

Please Remember:
•   Safe  travel in avalanche terrain requires training and experience. This avalanche 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.  
•   Expect a change in the avalanche danger when the actual weather differs from the higher summits forecast.  For more information, contact the U.S. Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or the Harvard Cabin.
•   A new advisory will be posted when conditions warrant.
 
Brian Johnston, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856