All forecast areas of Tuckerman Ravine have Considerable avalanche danger today. Natural avalanches are possible and human triggered avalanches are likely. Careful snowpack evaluation, cautious route-finding, and conservative decision making are essential.
Huntington Ravine has Considerable and Moderate avalanche danger. North, Damnation, and the Escape Hatch have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. All other forecast areas have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely.
Another wintery Mt. Washington weather event took place last night and is continuing this morning. Conditions are very blustery; snow is being blown around on winds which are currently gusting up to 100mph (162kph) from the West. Since the onset of snowfall around dusk last night through this morning, the Observatory has recorded 4.5″ (11.5cm) of new snow. This storm snow is the obvious driver of the Considerable rating today. Expect strong winds to create loading conditions in all forecast areas of both Tuckerman and Huntington Ravines. This will create a situation where naturally triggered avalanches are possible.
There are a couple things that you, the alpine traveler, have little control over today. One is whether or not you are able to see anything through the blowing snow and clouds. The other is that the slabs above you are developing and you can’t decide whether or not they fracture and fail. That decision is up to Mother Nature to figure out. We recommend choosing your route carefully and cautiously with this in mind. High pressure will take hold of the area today, but don’t expect clouds to clear out much before the afternoon. Also, since winds won’t die down until later tonight, blowing snow should continue throughout the daylight hours today and into the evening.
All around it will be a very “heads up” day if you’re looking to recreate in the ravines or above treeline. If you’re venturing up high on the mountain, you would be wise to prepare for blowing snow and very low visibility despite the incoming high pressure. We have opened the Lion Head Winter Route for the season. This is a steep mountaineering route, and we strongly recommend bringing an ice axe, crampons, and the ability to effectively use these tools.
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 8:45am, January 10, 2013. A new advisory will be issued tomorrow.
Jeff Lane, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856