Avalanche Advisory for Thursday, February 18, 2016

All forecast areas of Tuckerman and Huntington Ravines have LOW avalanche danger. Natural and human-triggered avalanches are unlikely. Watch for isolated pockets of snow in strong lee areas.

AVALANCHE PROBLEM: Tuesday brought over an inch of rain to the summit during a 12 hour period with temperatures above freezing. This liquid has since drained and refrozen leaving a widespread crust more capable of creating a long sliding fall problem than an avalanche problem. Add to that melt-channels, undermined ice and a lingering potential for ice dam ruptures in Huntington Ravine. In short, we’ll need to wait a day for an avalanche problem to arrive.

WEATHER: Temperatures have dropped steadily in the past 24 hours from the mid-teens F to -4F. A Low pressure system passed through northern Maine last night and grazed Mount Washington, dusting us with a 1/3” of snow. Currently, winds are from the west in the 30’s mph, with gusts into the low 40’s mph, under clear skies with some low clouds piled up to the west behind the Presidential ridge. Anticipate temperatures near 0F today with moderate NW winds in the 30-45mph range under clear skies most of the day. High pressure will bring continued clear and cold temperatures tonight and part of the day tomorrow until a Low pressure system brings some snow late Friday and into Saturday. The middle of next week brings a chance for more significant snowfall.

SNOWPACK: Old crown lines are still visible from the previous two avalanche cycles with wet slab debris piled up beneath Chute from the snow and rain event on Tuesday and the older crown in the Center Bowl through Lip eroded a bit and covered in place but still sticking out. There may be some new snow drifted up in places but should be easily identified and negotiated. The snowpack has drained out and is no doubt faceting to some degree around the new ice crusts with dry snow beneath the crust in places. The Headwall waterfall blew out the surface a bit and the Little Headwall which was very close to skiable on Monday is now refreezing into a low angle ice climb. As mentioned in the avalanche problem section, expect the ice climbs in Huntington Ravine to have some challenges created by Tuesday’s rain.

The John Sherburne Ski Trail has long sections of ice though, unlike yesterday, most areas of open water are now refrozen and passable. A few waterbars are still flowing and bare at lower elevations.

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 or the Harvard Cabin.
  • Posted 8:20a.m., February 18, 2016. 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

2016-02-18