Avalache Advisory for Tuesday, January 17, 2017

 

This advisory expires at midnight.

Tuckerman and Huntington Ravine have LOW avalanche danger. All forecast areas have Low avalanche danger. Natural and human-triggered avalanches are unlikely. In Tuckerman Ravine, Lower Snowfields and Little Headwall are not rated due to thin snow cover.

AVALANCHE PROBLEM: The current avalanche problem is Wind Slab that formed Sunday. This is from the 1” of snow blown around by strong west winds. These slabs are most evident in the Sluice, Lip, Center Bowl, and Chute in Tuckerman, while Huntington has almost no sign of them due to wind scouring. With snow arriving tonight, these slabs will become covered and not as easy to identify as they are this morning. Avalanche danger will increase with the incoming snow tonight. Be prepared to evaluate snow conditions if traveling after dark.

WEATHER: Yesterday was a sunny day on the hill. Today will start the same with mild temperatures in the 20sF, clear skies and NW winds around 40mph. As the day progresses, clouds will roll in and winds will shift to the south and decrease to possibly light and variable at times. Snow looks like it will begin around dark and continue overnight with the heaviest period of snow early tomorrow morning. It looks like the bulk of snow will be to our south, but we may see up to 8” by dawn tomorrow. Winds during this storm will remain from the south and likely stay under 30mph.

SNOWPACK: Firm, refrozen snow sums up much of the terrain above treeline. Even off trail, the thick crust is strong in most places to avoid postholing. Wind slab that exists in the steeper areas of Tuckerman may be soft, but it is relatively thin and sits on top of the same firm surface. Long sliding falls are again the main hazard today as the surface will be very hard to arrest a fall. Crampons and an ice axe are necessary in any terrain but the flats.

The Lion Head Winter Route is open and the most direct route to the summit from the east. Please be careful of bridge construction debris near crossover 7 on the Sherburne Trail when skiing or riding.

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 7:35a.m., Tuesday, January 17, 2017. A new advisory will be issued tomorrow.

Helon Hoffer, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2713

2017-01-17