Avalanche Advisory for Friday, April 1, 2016

Tuckerman Ravine has MODERATE and LOW avalanche danger. The Lip and Center Bowl have Moderate avalanche danger. Natural avalanches are unlikely and human-triggered avalanches are possible. All other forecast areas in Tuckerman Ravine have Low avalanche danger with natural and human triggered-avalanches being unlikely. Lobster Claw, the Lower Snowfields, and Little Headwall are not posted due to a lack of snow in these areas.

Huntington Ravine is under a General Bulletin. You will need to do your own snow stability assessments when traveling in avalanche terrain in Huntington. A danger of falling ice exists, and will persist until it all comes down.

AVALANCHE PROBLEM: A remote threat of Wet Slab avalanches is the primary avalanche concern due to rain further saturating our snowpack or waterfalls spilling out of their channels and into the snow. Heavy rain during potential thunderstorm activity combined with runoff from prolonged melting, could lead to a waterfall blowout from one of the larger drainages. It would be worth reducing time spent in Sluice through Chute in Tuckerman Ravine, along with the floor of the Ravine, despite the low likelihood of a wet slab avalanche. Wet loose sluffing could also be a problem on steeper slopes.

WEATHER & SNOWPACK: New snow that fell early this week has settled during the past 48 hours of warm weather, leading to reduced stability concerns. Prolonged high winds cresting at 133 mph from the west early Wednesday morning scoured most of Huntington Ravine and deposited hard wind slabs in strong lee areas. Warm temperatures yesterday softened snow on all aspects and lead to further settlement with no reported avalanche activity. Shockingly warm temperatures overnight have continued the melting and settlement trend reducing our stability concerns to pockets of untouched newer wind slabs from Tuesday along with the melt water induced wet slab mentioned above. An active weather pattern starts today with the first of several cold fronts swinging through, spawning rain showers and even some thunderstorm activity midday with .6” forecast by nightfall. Temperatures will drop below freezing overnight with showers of rain changing to snow.

Spring hazards you will most likely encounter given today’s weather forecast include:

  • Crevasses, moats and waterfall holes – Water flowing under the snow pack creates holes and thin spots in the snowpack above which can be deep enough to injure or kill.
  • Falling ice – This one is unpredictable. The best thing you can do is reduce your exposure by limiting the time you spend downslope from frozen waterfalls. Falling ice chunks can move with surprising speed and follow unpredictable trajectories. Rain increases the likelihood of falling ice and rocks.

The Lion Head Winter Route is closed. Please use the Summer Lion Head Trail.

Please Remember:

  • 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 8:00 a.m., Friday, April 1, 2016. A new advisory will be issued tomorrow.

Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2716

2016-04-01