This advisory expires at Midnight tonight.
Huntington Ravine has CONSIDERABLE and MODERATE avalanche danger. Central Gully has Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely. All other forecast areas have Moderate avalanche danger. Natural avalanches are unlikely and human-triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features. Evaluate snow and terrain carefully.
Tuckerman Ravine has CONSIDERABLE and MODERATE avalanche danger. Sluice, Lip, Center Bowl, and Chute have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely. Careful snowpack evaluation and cautious route finding are essential. Lobster Claw, Right Gully, Left Gully and Hillman’s Highway have Moderate avalanche danger. Natural avalanches are unlikely and human-triggered avalanches are possible. Evaluate snow and terrain carefully. Lower Snowfields and Little Headwall are not rated due to a lack of snow but look for overhead hazard in Lower Snowfields which remains mostly tree covered except beneath Duchess.
AVALANCHE PROBLEM: Less dense wind slabs formed by new snow since yesterday afternoon are something to look for and avoid today. Older, firmer wind slab which developed at the end of the nor’easter could also be a problem in the steeper, unsupported terrain. These slabs are certainly stubborn but if you draw the wrong card and find a thin spot, you could be the trigger for a large, hard slab avalanche. Steep but more protected terrain hold sensitive pockets more easily triggered by a person. These will be variable in size but could be consequential. Dry loose spindrift avalanches will add to the alpine experience on steeper climbs like Pinnacle Gully.
WEATHER: The temperature on the summit is a balmy 16F with wind from the west in the 50 mph range. The highest gust in the past 24 hours was 84 mph from the west. Snow showers are continuing this morning with around 3” on the ground at Hermit Lake which fell since late afternoon yesterday. Wind will increase to the 55-75 mph range and shift slightly to the northwest today. Forecast wind speed and direction will continue limited wind loading of available snow on the ground. Expect summit fog to challenge visibility through most of the day.
SNOWPACK: The snowpack yesterday was dominated by finger hard wind slabs as well as much thinner, softer four finger slabs. Beneath this surface layer, we found a softer layer of four finger plus to fist minus snow near the fork in Hillman’s and low near Right Gully and Lobster Claw. That upper layer continued to develop last night as new snow fell and was loaded into the terrain and is likely to be widespread through our forecast areas, particularly in the areas with a higher danger rating. There is a high degree of variability in the snowpack across the terrain right now so use safe travel techniques and evaluate the snow carefully.
The Lion Head Winter Route is open and the most direct route to the summit. The Tuckerman Ravine Trail bridge is completed enough to allow traffic again. Please be careful of construction debris near crossover 7 on the Sherburne Trail when skiing or riding.
- 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 7:35 a.m., Sunday, January 1, 2017. A new advisory will be issued tomorrow.
Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2713