Avalanche Advisory for Thursday, 4-25-2013

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.

Warm temperatures yesterday produced a bounty of corn snow which bordered on slush on southerly aspects. Overnight, temperatures dropped considerably (currently 21F on the summit) and winds have ramped up to the 60-80 mph (95-130 kph) range with the passage of a cold front.  Yesterday’s corn snow is now refrozen and practically unskiable.  Instead of corn snow, skiers and riders can expect frozen heads of cabbage on a steep, icy slope to be served today with little chance of being warmed by the sun into something rideable. Though winds will drop through the afternoon, it is unlikely that the magic combination of sunshine and warm temperatures will bring the corn snow back into shape for today, though the situation for the weekend looks promising. Yesterday’s warm temperatures (57 F or 14C at Hermit Lake) also sent some ice chunks down slope from the Center Bowl area and  further opened crevasses in the Lip so file this information away as we progress into the spring ski season. The waterfall hole at the Lip is still growing as well so give it, and other melt holes, a wide berth especially when warming conditions return.

Though temperatures will favor the bonding of ice today, continue to 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. The skiable section of trail is shrinking daily so you may want to leave the trail at an earlier cutoff than where it hangs now above the switchbacks.

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 8:00 a.m., April 25, 2013. 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

2013-04-25 Print friendly