Avalanche Advisory for Tuesday, 4-3-2012

This advisory expires at 12:00 midnight, April 3, 2012

Tuckerman Ravine has Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. The Lobster Claw, the Lower Snowfields, and the Little Headwall are not posted due to lack of snow. Huntington Ravine is under a General Advisory. You will need to do your own snow stability assessments when using avalanche terrain in Huntington. A danger of falling ice exists, and will persist until it all comes down.

With the exception of pockets of new snow in numerous places, recent snows have made little progress developing new slabs across large areas. On Sunday night, Mt. Washington received about 4.4” of very light density snow. Yesterday we thought this snow might be loaded into unstable slabs in the lee areas of Tuckerman. Although there was significant amounts of blowing snow along the ridges yesterday, slab development in the ravine was kept to a relatively small amount. There are isolated areas of newly deposited windslab. Each one you travel through may be different than the last, and they may be reactive to human triggering, so you should be assessing them individually. Additionally, be thinking about the fall line and runout. A small slab that knocks you off your feet may not bury you, but the consequences of a fall can be severe.

Currently, the springtime hazards are a little different than most years, due in large part to the thin snow coverage this season. Crevasses, undermined snow, and waterfall holes are a serious threat. Currently the area from the Sluice to the Center Bowl is littered with crevasses. Most of these are covered with a thin coating of newer snow, which makes them nearly impossible to safely assess their exact location and depth. The hazards presented by the crevasses are not to be taken lightly; it is truly “no-fall” terrain. Taking into account the extent of crevasses, the severity of the consequences, and the inability to assess the hazard, I highly recommend avoiding the Lip area entirely, which includes the area of Tuckerman Ravine hiking trail.

Surfaces will be icy and hard below the new snow, so long sliding falls continue to be another significant threat. The slick surface will allow for rapid acceleration down slope, potentially sending you into numerous obstacles below you. An ice axe, full 10-12 point crampons, and real mountaineering boots are absolutely critical for climbing in these conditions safely. The hard surface beneath the new snow makes belayed climbing on the steeper slopes a wise technique.  Because the current surface conditions have made most steep slopes “no fall” territory, the ability to use technical mountaineering skills and equipment effectively is imperative.

Even though temperatures this week will not be very warm, falling ice is a possibility as sun heats the dark colored rock. There is a lot of recently formed ice from the cold weather over the past couple weeks. Your best defense against falling ice is to avoid being anywhere near the possible runouts. The locations at greatest risk for this hazard are the Sluice, Lunch Rocks, the Lip, and the Center Bowl. Other areas aren’t immune though, so always be aware of what’s above you.

The Harvard Cabin is now closed for the season. The only camping permitted in the Cutler River Drainage is at Hermit Lake Shelters. The Sherburne Ski Trail is open about 1/3 of the way down and is in surprisingly good shape. Cross over to the hiking trail at the rope.

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, the caretaker at Hermit Lake Shelters.
  • A new advisory will be issued tomorrow.

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

2012-04-03 Print Friendly