Avalanche Advisory for Monday, April 2, 2018

Huntington and Tuckerman Ravine have LOW avalanche danger today. All forecast areas have Low avalanche danger. Generally safe avalanche conditions exist. The Little Headwall is no longer forecast due to a lack of snow.

AVALANCHE PROBLEM: Avalanche concerns today are limited to very isolated pockets of wind slab. The half inch of snow that fell yesterday was subjected to strong west winds that likely blew much of this snow down and out of avalanche terrain. Terrain features in the lee of this wind may have collected enough blowing snow to create small pockets of wind slab, but these will be easily identifiable by their white appearance when compared to the gray melt-freeze crust that developed from Friday’s rain. This melt-freeze crust is strong and supportive thanks to cold temperatures over the weekend and presents the greatest threat of the day in the form of long, sliding falls. While two skiers experienced this sort of fall on the Lip yesterday and walked away with no injuries thanks to a clean run-out, the result could have been much different if this had occurred in Left Gully or Huntington, places that have bushes or rocks to contend with. The Little Headwall may present similar today as open holes in the main riverbed are forcing skiers to make an icy traverse above an ugly open hole. It is possible to descend by traversing through the trees into the Lower Snowfields, but the general consensus was that this felt sketchier than any skiing in the Bowl and walking down to Hermit Lake looked like more fun.

WEATHER: Summit fog lingered for the day yesterday with strong wind and occasional snow flurries delivering 0.5” of snow. Wind was largely from the west between 60-80mph. High pressure moved into the region around midnight, allowing wind speeds to drop to a current W 22mph where they should linger for the day. Skies should clear as the day progresses though low level moisture may bring a return of summits fog in the afternoon hours. Temperatures will increase through the day from a current 5F to the 20sF by early afternoon.

SNOWPACK: The surface of our snowpack consists of a thick (16cm) melt-freeze layer that formed after 0.75” of rain saturated the snow surface and then refroze. Slopes that face north or east are largely smooth while south-facing slopes have refrozen with an uneven surface due to skiers and climbers enjoying the few hours of spring conditions that appeared Saturday afternoon. With temperatures on the summit reaching into the 20sF today, mild winds and clearing skies, there is a chance south-facing slopes will soften. That being said, watching the Lip go from peel-away corn to ice on Saturday afternoon when clouds rolled in and the sun disappeared behind Boott Spur was a good reminder of why the term flash-freezing exists. Despite being April, savvy travelers will still bring crampons and an ice axe on their ski adventure.

The Harvard Cabin is now closed for the season. The only place to camp in the Cutler River Drainage is 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  7:45 a.m., Monday, April 2, 2018. A new advisory will be issued tomorrow.

Helon Hoffer, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2858

2018-04-02