Avalanche Advisory for Wednesday April 24th 2013

This advisory expires tonight at 12:00 midnight.

Tuckerman Ravine has Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. Huntington Ravine is not posted. We are no longer monitoring conditions in Huntington this season. You will need to do your own snow stability assessments. A danger of falling ice exists and will persist until it all comes down.

As the spring season moves along it’s all about timing and location.  Whether you’re buying a house or playing in the mountains you need to know your real estate to stay on top.  First, consider the timing.  Watching the weather forecasts from day to day is one of the best ways to help yourself enjoy good spring ski conditions rather than hiking up into an icy *&%#$@.   As an example let’s look at today’s conditions. Temperatures on the summit have been rising slowly over the past 24 hours and are already above freezing.  The Ravines are even warmer, sandwiched between cold air aloft and cold air down low at Pinkham Notch.  Temperatures should continue to crawl higher today which will help soften overall snow conditions, particularly south facing slopes as the sun peaks out through the clouds.  However, as a cold front approaches from the west temperatures will fall rapidly tonight, changing the associated frontal moisture from rain to light snow.  The mercury should continue to fall tomorrow likely keeping surface conditions very hard.  This is a classic scenario that plays out through the spring.  Although isolated icy conditions can exist on warmer days, monitoring the forecasts and executing your timing can help substantially to avoid one of our greatest hazards-long sliding falls!  Falls are a serious hazard and many past incidents have turned out very badly, but you are in complete control to prevent this potential accident. Between timing the temperatures and snow hardness relationship, having the skills to use your mountaineering ax and crampons, and staying within the limits of your climbing ability given the conditions can all greatly mitigate this fall hazard.

As you time temperatures for softer snow realize warm conditions are increasing our other hazards.  So although these hazards have an inverse timing relationship you can start using location choice to protect yourself.  As conditions warm the risk of falling ice, undermined snow, and developing crevasses all grow so keeping yourself away from these issues is critical.

Be wary of ice hanging over the approach to the Sluice and Center Bowl.  This ice will fall down in large chunks that roll unpredictably and with surprising speed.  Don’t linger at Lunch Rocks or on the floor of the ravine in these run out zones.  Hanging out under the ice is a game of Russian roulette.  Some days there are more rounds in the chamber than others but why play those odds at all if you don’t have to. Choose your routes carefully to reduce exposure to this hazard.

Crevasses have opened and will continue to open as our snowpack creeps downhill.  The slab of snow marking the climber’s right edge of last Friday’s wet slab avalanche has a developing crack near the top. This slab is unsupported and is close to 6′ thick on a slope approaching 50 degrees. Though an avalanche here is unlikely, it is not impossible.   Crevasses are forming in the Sluice, Lip and Center Bowl areas. These slots can be deep and have been the scene of many accidents in the past, some of which were fatal. Give the crevasses and areas around any ice a wide berth.

The Sherburne Ski Trail is closed about 0.75 miles uphill of Pinkham Notch. At the rope, you will need to cross over to the hiking trail and walk down to the parking lot. PLEASE do not walk or attempt to ski down this muddy trail below the rope as it isn’t built for foot travel, will contribute to the erosion of this trail, and cover you with wet mud.

Forest Service snow machines have been put away for the year and Snow Rangers are not on the mountain everyday due to other responsibilities on the White Mountain National Forest.  Though we are closely monitoring conditions and are ready to respond to incidents, our response time will be greatly increased.  As always, you need to be ready to initiate and carry out your own rescue effort so be prepared with the knowledge and equipment to effectively help yourself or someone else in your party.

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 Mount Washington Volunteer Ski Patrol, or the AMC at Pinkham Notch Visitor Center.
  • Posted at 7:30 a.m., April 24, 2013. A new advisory will be issued tomorrow.

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

2013-04-24 Print Version