Expires at 12:00 midnight Tuesday, December 31, 2013.
Tuckerman Ravine has MODERATE and LOW avalanche danger. The Sluice, Lip, Center Bowl, and Hillman’s Highway have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. Lobster Claw, Right Gully, Chute, Left Gully, Lower Snowfields, and Little Headwall have Low avalanche danger. Natural and human triggered avalanches are unlikely. Watch for unstable snow in isolated terrain features within these locations.
Huntington Ravine has MODERATE and LOW avalanche danger. Central Gully, Pinnacle, and Odell have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. All other forecast areas have Low avalanche danger. Natural and human triggered avalanches are unlikely. Watch for unstable snow in isolated terrain features within these locations.
AVALANCHE PROBLEM: Windslabs leftover from yesterday’s howling winds are the problem of the day. Many of our forecast areas were hit hard by the winds and had their snow removed either by avalanche activity or by scouring action. These are currently rated Low and offer the best opportunity to avoid unstable snow in steep terrain. However, in these areas you should be on the lookout for smaller pockets that may harbor unstable snow. The areas rated Moderate were the most protected against the strong W winds and have greater potential for someone to trigger an avalanche.
WEATHER: It’s a calm, clear, and cold morning today, but this may only be a brief window of good weather before clouds lower and engulf the mountain by late day. Winds will be on the increase, rising to 40-55mph (64-89kph) by dark. Additional snowfall up to 2” may come, but should hold off until late in the day. New snow falling with expected wind speeds will start to form new windslabs; this may become a problem if you are out on the mountain after dark.
SNOWPACK: Despite getting a 12” storm just two days ago and a total of 66” for the month at the Summit, overall snow coverage in both ravines is still pretty thin. This is due in large part to a lack of snow in October and November, and also to the thaw from about a week ago. Yesterday’s 103mph peak gusts removing snow from Huntington can also be a factor in the overall thin cover. Our snowpack is still very discontinuous, even in some of the most protected terrain such as the Center Bowl. As usual, there is a lot of variability as you move around. The crust that formed a week ago is currently the most likely bed surface for any avalanche activity. Above this you’ll find a variety of conditions, including some areas that are strong and some that are weak.
- 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 8:30 Tuesday. Tuesday, December 31, 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