Avalanche Advisory for Monday, February 6, 2017

Huntington Ravine has MODERATE and LOW avalanche danger today. Central, Pinnacle, Odell, South and Escape Hatch have Moderate avalanche danger. Natural avalanches are unlikely and human-triggered avalanches are possible. All other forecast areas in Huntington have Low avalanche danger. Natural and human-triggered avalanches are unlikely.

Tuckerman Ravine has MODERATE and LOW avalanche danger today. Sluice, Lip, Center Bowl, and Chute currently have Moderate avalanche danger. Natural avalanches are unlikely and human-triggered avalanches are possible. Lobster Claw, Right and Left Gullies, Hillmans Highway, Lower Snowfields and Little Headwall have Low avalanche danger. Natural and human-triggered avalanches are unlikely.  Open water and ice remain exposed in the Little Headwall and the creek above. It is skiable but people have been occasionally punching through into water beneath.

AVALANCHE PROBLEM: Wind slabs have once again made a comeback as our primary avalanche problem. Even in the steepest and most wind-sheltered areas rated at “moderate” avalanche danger, the slabs will be stubborn to trigger but a weak layer of softer snow does exist beneath. Smaller pockets of softer wind slabs are also scattered around the terrain, mixed with the predominately firm slab. Yesterday, most surfaces were just bootable and edge-able but crampons are a good call due to the wind hammered nature of the slabs. As history shows, even the inch of snow forecast through the day on diminishing winds can drift into pockets of wind slab. Some skiable and rideable snow will exist today but in limited amounts in areas well sheltered from the high, westerly winds. Hard wind slabs of most concern may be found in the steepest terrain with drifts and sluff piles.

WEATHER: Current temperature at Pinkham Notch is 11F with 1.5” of new snow in the ground. The summit recorded 1.5” of snow overnight also with a current temperature of -8F and winds blowing from the WNW in the 65 mph range. Winds will continue to drop off a bit through the day after gusting to near 90 mph last night. Expect cold temperatures, with a high around 0F or just below on the summit with diminishing winds remaining in the 50-70mph range. Summit fog may clear a bit today and allow for improved, but not good visibility.

SNOWPACK: Recent wind velocities on the mountain have firmed up our surface slabs and made for less than ideal skiing and riding conditions. Cramponing up these slopes in the firm snow seems to be the better option though a patient and a calculated approach could result in a win for skiers in some sheltered terrain. Lots of scouring has occurred over the past 48 hours in many areas such as northern Huntington gullies, Left and Right gullies and the lower reaches of Hillmans Highway and the floor of Tucks. Between cold temperatures, strong winds, and reduced visibility, it seems like a good day to review forecast models for tomorrow’s approaching storm. Currently, 5-9” or more snow is forecast, with a southerly wind direction early in the storm. Orographic enhancement may increase snowfall to a foot. The main question is to what extent freezing rain early Wednesday morning will reach our forecast elevations, though at this time, things look promising for only a bit of ice accumulation.  Areas with a northerly aspect will continue to outpace south facing gullies in terms of total snowpack coverage as they have since the last nor’easter on December 29th filled north facing terrain.

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  8:15 a.m., Monday, February 6, 2017. A new advisory will be issued tomorrow.

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

2017-02-06