This advisory expires tonight at 12:00 midnight.
Tuckerman Ravine has High and Considerable avalanche danger. Travel in avalanche terrain is not recommended. The Lip, Center Bowl, Chute, and Left Gully have High avalanche danger. Very dangerous avalanche conditions exist. Natural avalanches are likely and human-triggered avalanches are very likely. All other areas have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely. The Lower Snowfields and Little Headwall remain not posted.
Huntington Ravine has High and Considerable avalanche danger. Central Gully has High avalanche danger. Very dangerous avalanche conditions exist. Natural avalanches are likely and human-triggered avalanches are very likely. All other areas have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely.
AVALANCHE PROBLEM: Today will start with elevated avalanche danger, and today’s weather will bring still increasing danger. Wind slabs will be building on all aspects. If the ravine elevations transition to rain in the early morning, avalanche danger may quickly spike, particularly in N-facing or NE-facing slopes. If precip stays as snow, the problem early in the day will be dominantly on the same N and NE-facing slopes, but as winds increase and wrap toward the W and NW, all forecast areas will be loaded with wind-transported snow. The flat terrain at the base of Tuckerman and on the fan in Huntington are well within striking distance of avalanche activity today. Do not assume it is safe to go to the ravine “just to take a look.”
WEATHER: We are in the grips of a winter storm this morning. So far, 6″ (15cm) of 13% density snow has fallen at Hermit Lake. While it is rain and freezing rain down in the valley, upper elevations have remained cold and snowy so far. This may change in the next couple hours, before temperatures begin to fall off again in the afternoon. The greatest chance for rain in the ravines will be in the morning hours. As winds increase today they will be shifting from S to W and eventually to the NW. The snow that has fallen in the alpine zone will be transported into the steep slopes of Tuckerman and Huntington.
SNOWPACK: Your avalanche assessments today should be focused on the weather that is currently taking place and the wind loading we expect to see later. Wind speeds and directions will play a significant role in how the avalanche danger grows. This is the kind of day where splitting hairs between the differences in various weather forecasts will quickly bring you farther into the weeds than you ought to be. Keep it simple – wind loading will be taking place on a wide variety of aspects. The day is just starting and we already believe we have significant avalanche issues, especially if we get rain in the ravines. The risk of naturally triggered avalanches will continue until the precipitation drops off and winds abate, likely sometime tomorrow.
- 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 8:15am, March 2, 2016. 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