Avalanche Advisory for Friday, April 8, 2016

Tuckerman Ravine has MODERATE avalanche danger. Natural avalanches are unlikely and human-triggered avalanches are possible in all forecast areas. Evaluate snow and terrain carefully. Lobster Claw, Little Headwall and Lower Snowfields are not posted due to lack of snow.

Huntington Ravine is under a General Bulletin. You will need to do your own snow stability assessments when traveling in avalanche terrain in Huntington. A danger of falling ice exists, and will persist until it all comes down.

AVALANCHE PROBLEM: Today’s avalanche problem will be in the form of wind slabs. Snow shower activity this morning, coupled with upslope snow showers this afternoon, may produce 2-4” of snow. This new snow will be falling on a refrozen rain crust with wind speeds in the 30-45mph range. Wind slabs sensitive to human-triggering may form in lee areas of a southwest wind and crossload in other areas. If wind and snow remain on the lighter side, expect only pockets of unstable snow. Snow totals near 4” with wind speeds at the upper end of the forecast velocity could develop larger areas of wind slab that will be harder to avoid.

WEATHER and SNOWPACK: There will be lots of refrozen old surface in our terrain due to the heavy rain that ended early this morning.  This storm dumped 2” (52mm) of rain at Hermit Lake with 1.12” rain and a mixed bag of frozen forms of sleet and wet snow on the summit. Streams are raging with snowmelt and though there is little in the way of visibility this morning, it is likely that the waterfall holes in the Lip are showing like gaping wounds. Clearly our already meager snowpack has taken another beating as evidenced by 12cm of settlement at the Hermit Lake snow stake since Tuesday. Today winter will begins its steady march back into the region with temperatures on a steady decline that will lock up our deeper snowpack and throw away the key for the weekend. Temperatures will reach down to the mid-teens later today and just above 0F overnight. Snow showers have begun at Hermit Lake this morning with lots of snow shower activity moving our way on the radar. Clouds and snow showers will reduce visibility and flatten out the light. I don’t expect you’ll find good skiing on stable snow today considering that the total snowfall amounts are unlikely to bury the icy bed surface enough to resist being scraped off during a turn. Other hazards you’ll encounter today include:

  • Long sliding falls – Crampons are highly recommended in steep terrain. Snowshoes and microspikes are no substitute. Expect a variable snowpack with some new snow falling on a firm surface with limited boot penetration. Arresting a fall on a steep slope can be practically impossible, even with an ice axe.
  • Crevasses, moats and waterfall holes – Warm water flowing under the snow pack creates holes and thin spots in surface that are deep enough to injure or kill you. New snow can drift and obscure the openings.

The Sherburne Ski Trail is now closed at #7, allowing about 2/3 mile of skiing from Hermit Lake. Expect exposed ice. The Harvard Cabin is closed for the season. The only camping permitted in the Cutler River Drainage on the east side of the mountain will be at Hermit Lake Shelters.

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.
  • Posted 8:30 a.m., Friday, April 8, 2016. A new advisory will be issued tomorrow.

Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2716

2016-04-08