Avalanche Advisory for Sunday, February 16, 2014

This advisory expires at Midnight

Tuckerman and Huntington Ravine has CONSIDERABLE avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. Dangerous avalanche conditions exist. Careful snowpack evaluation, cautious route finding and conservative decision-making are essential.

AVALANCHE PROBLEMS:  Not surprisingly, Wind Slab is the primary avalanche problem today.  New snow overnight has blown into both ravines forming dangerous wind slabs over existing wind slabs. Low visibility will make it challenging to assess slopes and avalanche paths above you. Wind speeds will increase today, further loading slopes in the lee of the northwest wind. Recent avalanche activity has filled in and smoothed out avalanche paths creating the opportunity for natural avalanches to run well into low angled terrain in both ravines. So far, winds are ideal for loading with little scouring so many areas are solidly Considerable.

WEATHER:  Steady northwest winds blowing in the 70-80 mph range, potentially gusting to over 100 mph, will make travel extremely difficult today. Evidence of snow loading appears right out of Pinkham Notch with wind drifts peppering the trail and frequent plumes of snow being picked up off the ground. In addition to some old snow being picked up and blown, 4″ of new snow fell since 6pm yesterday creating a new wind slab problem. Temperatures are currently -10F (-23C) on the summit and 2F (-17C) at Hermit Lake. One skier appeared in Hermit Lake courtyard with a quarter sized white patch on his nose that developed in the ten minutes of exposure to the wind outside the lean-to. Conditions are pretty inhospitable on the mountain today…an ideal location for a super villains lair.

SNOWPACK:  Fieldwork yesterday revealed fair stability on south aspects with wind slabs in the upper snowpack failing in the CT easy range on multiple layers in 10 different tests in 4 locations though the failures were generally Q2. More troubling was a weak interface 90-100cm down. Though deep enough that accessing it would require really rotten luck, finding a thinner area in the snowpack to act as a trigger point while hiking or skiing is easily conceivable. New loading today, particularly in areas which didn’t appear to slide or slid early Thursday/Friday, like Center Bowl and Central, could push us beyond the tipping point naturally today with no human trigger needed. As mentioned earlier, avalanche paths developed further during the Thursday/Friday avalanche cycle. Lobster Claw ran just to the floor in it’s first avalanche of the year and is now a narrow but continuous run from the rim. Right Gully and Sluice both avalanche and piled debris to the top of the Lunch Rocks rescue cache. Debris from a Lip avalanche alomst completely buried the Open Book. Surprisingly, Center Bowl debris wasn’t evident so it would not surprise me at all to see a fairly large avalanche sweep out of there and into the floor today with the new loading. Central Gully approach, South Gully and Escape Hatch were all well loaded and plump yesterday so and ripe for a human trigger should someone attempt to travel through these areas today.

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 8:45 a.m. 2-16-2014. 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

2014-02-16 Print friendly