Avalanche Advisory for Sunday, April 17, 2016

This advisory expires at midnight.

Tuckerman Ravine has LOW avalanche danger. Natural and human-triggered avalanches are unlikely. Lobster Claw, Lower Snowfields and Little Headwall are not posted due to lack of snow.

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: The multiple melt-freeze cycles that took place over the past week have created a stable snowpack, eliminating most avalanche problems. Concerns about skier-induced sluffs and wet loose avalanches are less today than yesterday as just about all skiable terrain saw traffic. The most present danger today will be the several objective hazards that must be recognized for safe travel:

  • Falling ice – Large, falling ice chunks can move with surprising speed on destructive, unpredictable trajectories. The best thing you can do to reduce your exposure to this hazard is by limiting the time spent below these frozen waterfalls. “Icefall Rocks” (Lunch Rocks) and beneath Center Bowl (the Headwall) are in the crosshairs and are a bad place to sit, sled or hang around in. Sitting down lower on the Ravine floor near the entrance to the bowl is a great alternative to hanging out in “Icefall Rocks”.  Expect the falling ice hazard to increase as sun warms the Ravine.
  • Crevasses, moats, and waterfall holes – Water flowing under the snow pack creates holes, glide cracks (crevasses) and thin spots that are deep enough to injure or kill you. The climber’s right side of the Bowl, near and under “The Lip”, harbor the most and deepest holes.
  • Long sliding falls – Crampons, an ice ax, and the experience and skills to use them effectively can be essential to travel safely in steep terrain. Snowshoes and microspikes are not a substitute and just “following the boot pack” is risky. Watch the runout in your potential fall line to pick a route that avoids frozen waterfall cliffs and rocks. The thin nature of the snowpack at the moment is creating unusual bootpacks, often traversing the fall line and creating traffic jams with skiers.

WEATHER and SNOWPACK: Bluebird weather will continue allowing for another beautiful day on the mountain. North shifting NW winds will start today at 10-25mph and increase to 20-35mph. With temperatures in the low 40sF on the summit, expect all surfaces to soften throughout the day. Yesterday, all skiable surfaces saw traffic, with some of the areas previously untouched seeing skier induced sluffing that ran to the floor of the Bowl. Today, the various spring hazards will be at the forefront of my mind with icefall topping the big three. The low snowpack never covered a large amount of ice that now sits hanging above the floor of the ravine. The icefall potential will linger until it all comes down. Several skiers at the end of the day struggled with their last run due to the shade flash-freezing the snowpack. If debating whether or not to make one more run, keep in mind that anything in the shade will be vastly different than the hero corn that existed during the height of the day.

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.
  • Posted 8:00 a.m., Sunday, April 17, 2016. A new advisory will be issued tomorrow.

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