Avalanche Advisory for Monday, March 28, 2016

All forecast areas of Tuckerman and Huntington Ravines have LOW avalanche danger. Natural and human-triggered avalanches are unlikely. Lobster Claw, the Lower Snowfields, and Little Headwall are not posted due to a lack of snow in these areas.

AVALANCHE PROBLEM: A remote threat of Wet Slab avalanches is the primary concern later this morning due to rain further saturating our snowpack or waterfalls spilling out of their channels and into the snow. Our snowpack warmed and settled quite a bit over the past few days, but heavy rain could lead to a waterfall blowout or a deeper wet slab on an ice crust. Sluice through Chute in Tuckerman Ravine, along with the floor of the Ravine would be a good place to not linger today despite the low likelihood of a wet slab. Depending on how soon precipitation changes over to snow, some wind slabs may develop in the late afternoon.

Ice fall hazard, undermined snow and widening crevasses emerged as more significant threats particularly in the Lip area. Heavy rain today will again increase the risk of these potential threats. New snow can cover and hide crevasses and waterfall holes.

WEATHER: Rain will begin to fall mid to late-morning as a Low pressure passes through the area while temperatures remain above freezing. Rainfall is likely to be heavy at times before changing over to frozen precipitation types. Temps will drop through the day as cold air nudges in beneath warm upper level air. A period of freezing rain will result mid-day before a cold front becomes established over the mountains. Moderate southerly winds, in the 40 mph range on the summits, will ramp up and shift to the west later in the afternoon as snow develops. A combination of weather factors is in place for a solid upslope snowfall tonight and tomorrow on the heels of the cold frontal passage. High winds will develop through the night.

SNOWPACK: Warm daytime temperatures and sunny skies led to great corn skiing for folks over the weekend with even shady aspects softening yesterday. The prolonged warm temperatures and rain on Friday on our well settled snowpack reduced the concerns we had last week about deeper buried weak layers being players in our avalanche problems. Today’s weather will make it a worthwhile day to find something to do besides spending time in the mountains. Soaking heavy rain will make things pretty miserable though the day and freezing rain in the afternoon won’t make things much better. Trails in the area will return to their season default of wall-to-wall ice before some snow cover improves things though it is uncertain how low in elevation this will happen.

The Lion Head Winter Route is closed. Please use the Summer Lion Head Trail.

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 7:50 a.m., Monday, March 28, 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

2016-03-28