Avalanche Advisory for Wednesday, April 19, 2017

This advisory expires at Midnight.

Huntington and Tuckerman Ravines have LOW avalanche danger. Natural and human-triggered avalanches are unlikely. Generally safe avalanche conditions exist. The Little Headwall is now a waterfall with open holes and thin snow bridges above.

 AVALANCHE PROBLEM: Continued freeze/thaw cycles have reduced avalanche concerns today. Freezing conditions overnight have frozen the snow surface which will create a different set of concerns for safe travel today that will replace the more typical skier-generated wet-loose sluff problem. Long, sliding falls will be more of a concern due to the hard surface conditions that exist this morning. Snow may soften later in the day but thick cloud cover will delay this process.

 WEATHER: The current temperature on the summit is 20F with a west wind in the mid-30’s mph, gusting to 40. Winds will shift to the southwest and increase to 45-60 mph. Clouds will increase with an approaching warm front which could generate some snow showers this afternoon before turning to rain or mixed precipitation later in the day. Temperatures will rise to the low 30’s F on the summit, warmer at Ravine elevations, which will allow continued melting this afternoon and overnight. Rain shower activity will continue overnight.

Be aware of the following hazards today:

  • Long sliding falls – Crampons are highly recommended in steep terrain. Snowshoes and microspikes are no substitute. Arresting a fall on an icy 30+ degree slope can be practically impossible, even with an ice axe. Any slip could potentially turn into a slide for life and could put you into a glide crack or waterfall hole.
  • Crevasses or glide cracks, moats and waterfall holes – Warm water flowing under the snow pack creates holes and thin spots in surface that are deep enough to injure or kill you. New snow can drift and obscure the openings. Glide cracks, our version of crevasses, form when the snowpack gradually creeps downhill. As the snow pulls away from a cliff, this creates a gap that could swallow a person. The glide cracks are becoming more widespread and a number of them are now big enough that someone could disappear into one. The waterfall hole in the Lip is growing each day and has a long history of acting in unpredictable ways. This particular hazard is best given a wide berth.
  • Icefall: This hazard is unpredictable but above freezing temperatures certainly increase the risk of ice releasing from a cliff. Ice falls, rolls and slides with surprising speed at times. Don’t count on your ability to dodge this hazard. It is best to reduce your risk by reducing time spent beneath frozen waterfalls. As we move forward, remember that Lunch Rocks is in the bullseye of the massive ice in Sluice which makes hanging out there a high stakes game of roulette.

The Little Headwall is now more water than snow and is no longer recommended as a descent from The Bowl. The easiest and fastest descent is to hike down the Tuckerman Ravine Trail to Hermit Lake before skiing or riding. The Sherburne Ski Trail is melting fast and much of the trail close to Pinkham is mostly dirt and grass. In order to prevent erosion problems, please remove your skis and walk from the rope at crossover #3.

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 caretaker at Hermit Lake Shelters.

Posted  8:20 a.m., Wednesday, April 19, 2017. A new advisory will be issued tomorrow.

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

2017-04-19