Avalanche Advisory for Thursday, January 26, 2016

This advisory expires at Midnight.

Tuckerman and Huntington Ravine have LOW avalanche danger. All forecast areas have Low avalanche danger. Natural and human-triggered avalanches are unlikely. Watch for unstable snow on isolated terrain features. In Tuckerman Ravine, the Little Headwall is not rated due to thin snow cover.

AVALANCHE PROBLEM: The main concern today will be loose-dry avalanches in steep terrain today. These avalanches could be very heavy due to the high water content of recent precipitation and could cause some significant problems over a bad runout, cliff or terrain trap. Primary locations would be beneath steep terrain where sleet mixed with snow may have pooled deeply as well as areas with a north facing lee component like Escape Hatch, South and Hillman’s Highway. An icy glaze capping the snow and 24 hours of conditions favorable for settlement have reduced our propagation concerns that could lead to the fracture of a wind slab but limited visibility and field observations does create some uncertainty. Travel carefully despite the rating today.

WEATHER: No new snow has been recorded in the past 30 hours though some blowing snow was observed for an 8 hour period yesterday evening. Given the density of the existing snow and ice glaze on the ground, it is likely that not a lot was transported into our avalanche start zones. Lingering moisture resulting in a low cloud cap are currently reducing visibility. This situation is unlikely to improve as a passing cold front will bring more clouds with snow showers this afternoon. Current temperature at Hermit Lake is a balmy 34F but will drop to the mid-20’sF later today with mid-teens on the summit. West winds currently in the 35-50 mph range will increase to 50-70 mph with higher gusts. A trace to an inch of snow may fall during daylight hours with another 1-3” tonight.

SNOWPACK: The inch and half of snow water equivalent that fell Monday night and Tuesday fell in an upside down configuration that would have created much greater avalanche problems had it not fallen on 80 mph easterly winds. Much of the early, lighter snow appears to have been either scoured out, wind packed into denser slabs, or had any energy, reactivity or propagation potential crushed out of it by subsequent wet snow, sleet, and a cap of freezing rain. Reports from a skier up Right and down Lobster Claw indicate a breakable crust over granular snow and sleet that has pooled deeply in places. The crust was supportable and edgeable on skis and allowed a survivable trip down Lobster Claw. Right Gully was predominately scoured.

The Lion Head Winter Route is open and the most direct route to the summit from the east. Please be careful of bridge construction debris near crossover 7 on the Sherburne Trail when skiing or riding.

Continued internet access problems again today resulted in a hasty trip back to Pinkham Notch to post this advisory. Apologies for the delay!

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  8:20a.m., Thursday, January 26, 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

2017-01-26