Avalanche Advisory for Tuesday, January 19, 2016

This advisory expires tonight at 12:00 midnight.

All forecasted areas of Tuckerman Ravine have Considerable avalanche danger. Dangerous avalanche conditions exist. Natural avalanches are possible and human triggered avalanches are likely. The only exceptions to this are the Lobster Claw, Lower Snowfields, and Little Headwall which remain not posted due to an overall lack of snow in these areas.

Huntington Ravine is under a General Avalanche Bulletin. General Bulletins are issued when instabilities are isolated within forecast areas and are issued every three days or earlier if conditions warrant. Forecast areas in Huntington have less well developed snowfields to produce avalanches. However, bed surfaces do exist, particularly in Central, Pinnacle, Odell, and South gullies. Climbing today in Huntington will be very challenging due to weather and very poor visibility. You will not be able to visually assess the routes for avalanche potential before you have already exposed yourself.

AVALANCHE PROBLEM: Wind slabs are the primary threat again today. Although snow stopped falling throughout much of the region a while ago, on Mt. Washington, wind transport of recently fallen snow is causing elevated avalanche hazard. Additional upslope snow is expected today which will mix with the blowing snow as winds remain remarkably strong. These factors lead us to believe there will be numerous avalanches in Tuckerman, with some paths possibly running multiple times. Poor visibility will limit your ability to assess your location in relation to the avalanche runout paths. Expect runouts to be farther than they have been yet this season.

WEATHER: Strong winds in excess of 100mph (161kph) will be buffeting the mountain throughout the day while temperatures stay brutally cold. Be cautious if traveling in the mountains, even below treeline. Upslope snow showers will take place today, hopefully giving us a few more inches of snow. The Obs is calling for 1-3″, but the NWS has made mention of 4-6″ possible in the notches and northern Coos county. I won’t hang my hat on the potential for 6″, but be aware that it will be snowing. The sunshine you’ll see in the valleys most likely won’t be found on Mt. Washington today.

Yesterday snow fell lightly though the day on W winds with increasing speeds. The Obs reports 5.5″, but they had blowing snow filling their can deeper than that, so exact numbers are uncertain. The same goes for our snowplot at Hermit Lake; drifting was widespread on our collection boards.

SNOWPACK: Due to persistent snow yesterday and the blowing snow today, we have not seen the mountain since Sunday afternoon. I expect we began an avalanche cycle yesterday which will continue today. Snow began on light winds in the teens (mph), leaving a weak layer which would have been loaded on top of by slab formed during the strong winds later in the day. This trend continues as of this morning. While we can’t say which areas may have already avalanched, I do believe today’s conditions are conducive to multiple avalanches in the same path. Hard slabs will be forming and building. When these release, their impressive density can send them farther down the paths than you might expect.

We are not posting Lobster Claw, Lower Snowfields, and Little Headwall due to an overall lack of snow. On Sunday, Lobster Claw was virtually 100% bushwhacking. I think (and hope) this will change dramatically with the amount of wind loading taking place today. Please do not assume that the lack of a rating means there is no avalanche potential whatsoever. It’s your responsibility to make your own assessments.

In Huntington, the General Bulletin remains in place. I believe we will have widespread scouring through most of the gullies, but again, this does not mean that avalanche activity cannot take place. It’s probably a good time to wait it out a little bit, let the clouds clear and the winds die down, and then see what things look like.

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 8:25 a.m. January 19, 2016. A new advisory will be issued tomorrow.

Jeff Lane, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856

2016-01-19