Avalanche Advisory for Friday, March 11, 2016

All forecast areas of Tuckerman Ravine have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely. Careful snowpack evaluation, cautious route-finding and conservative decision making are essential. Lobster Claw, the Lower Snowfields, and Little Headwall are not posted due to a lack of snow in these areas.

Huntington Ravine has Considerable, Moderate and Low avalanche danger. Central, Pinnacle, Odell, South, and Escape Hatch have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely. Yale has Moderate avalanche danger. Natural avalanches are unlikely and human-triggered avalanches are possible. North and Damnation have Low avalanche danger. Natural and human-triggered avalanches are unlikely.

AVALANCHE PROBLEM: Wet slabs and persistent slabs remain the avalanche problems today. Human-triggered avalanches will remain more likely than possible due to the recent warming trend and copious amounts of rain water still percolating down through the snowpack. Snow stability will improve through the day as temperatures continue to fall but will require very careful snowpack evaluation and cautious route-finding.

WEATHER: Skies will clear today as the low pressure system which brought over 1.25” of rain followed by 1.25” snow, snow pellets, and freezing rain to the summit moves offshore. In its wake, high pressure moving in is bringing falling temperatures which will drop to the mid-teens F on the summit by sunset. NW winds will increase a bit through the day, 50-55mph increasing to 55-60 this afternoon with gusts to 80mph. Thick fog still envelops the summit but should clear later in the morning.

SNOWPACK: The falling temperatures will ultimately bring stability to our snowpack and set the stage for reduced avalanche risk, but not until the rain, which just stopped falling at Ravine elevations, drains through the snowpack. Several ice crusts with weak layers of snow above and below them are driving our stability concerns at this point. Meltwater reaching these layers can weaken them and set the stage for large wet avalanches. Our stability is improving today but will demand a keen eye for snow stability and lots of digging around to determine if the heat has yet left the snowpack. I would recommend staying off of steep slopes and away from the runouts of avalanche paths until refreezing brings improved stability. Long-sliding falls will be a real threat later today and tomorrow as wet snow on the surface refreezes.

New snow that fell last week has melted off the Tuckerman Ravine Trail leaving ice in its place up to the Huntington Ravine Fire Road. The John Sherburne Ski Trail will likely be closed partway up tomorrow morning. Please respect the closure by walking over to the Tucks trail at the rope to reduce erosion on the 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 8:10a.m., Friday, March 11, 2016. A new advisory will be issued tomorrow.

Frank Carus/Helon Hoffer, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856