Avalanche Advisory for Saturday, January 31, 2015

This advisory expires at midnight.

Very dangerous avalanche conditions exist in Tuckerman and Huntington Ravines. Travel in avalanche terrain, including low angle terrain in the floor of the Ravines, is not recommended.

Tuckerman Ravine has High, Considerable, and Moderate avalanche danger. Sluice, Lip, and Center Bowl have High avalanche danger. Natural avalanches are likely and human-triggered avalanches are very likely. Lobster Claw, Right Gully, Chute, Left Gully, and Hillman’s Highway have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely. Careful snowpack and weather evaluation, cautious route finding and conservative decision making are essential. Little Headwall and the Lower Snowfields have Moderate avalanche danger. Natural avalanches are unlikely and human-triggered avalanche are possible.

Huntington Ravine has High and Considerable avalanche danger.  Damnation, Yale, Central, and Pinnacle have High avalanche danger. Natural avalanches are likely and human-triggered avalanches are very likely. North, Odell, South, and Escape Hatch have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely.

AVALANCHE PROBLEM: Wind slabs are the imminent threat today. New snow deposited on near calm winds yesterday will form a soft weak layer on which new wind slabs will form today. These slabs will continue to build through the day and could avalanche spontaneously from lee areas without a human to trigger them. Avalanche paths are developed to the point that avalanches will likely run out onto low angle and flat terrain therefore travel into the vicinity of the Fan in Huntington or into the floor of Tuckerman much beyond the Connection Rescue Cache is not recommended.

WEATHER: 5.5” (13.4cm) of new snow was observed on the 24 hour board this morning at the Hermit Lake snow plot. The summit recorded a similar figure that of 5% density snow which will be easily blown into our avalanche starting zones. It is a serious day to be in the mountains. High winds ramping up from 60ish mph to 75-95mph (121-153kph), gusting to 110mph (177kph), frigid temperatures around -5F (-21C), low visibility and elevated avalanche risk make it a very challenging day. I know I am only here so I won’t get fined.

SNOWPACK: Hopefully you are not thinking that areas rated Considerable are the better target for recreation today. Though the risk of natural avalanches in these areas is less than in areas rated High, you could still easily trigger a sizable avalanche. New snow over the past 24 hours has formed a sensitive weak layer with wind slabs on top that will be soft enough to trigger pretty easily. Today’s wind will ramp up and continue the process of creating denser slabs over a softer, weaker layer. Bear in mind too that there is still snow from the Tuesday event earlier in the week that will be available for transport due to the short period of time that high winds were able to effect it. Later today, wind velocities will increase to the point that snow deposited earlier during this storm cycle will begin to erode, especially in Huntington Ravine. Though the avalanche danger will diminish at that point, there many other factors that should make you consider your travel decisions very carefully.

The Lion Head Winter Route is open but will present a significant challenge today given the current weather conditions and forecast. A minor incident could turn into a life or death struggle.

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 8:15 a.m. January 31, 2015. A new advisory will be issued tomorrow.

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

2015-01-31 print friendly

One person’s Snowpocalypse is another person’s good day in the mountains…..

As promised, this morning, I have a some opinions to share on the Patriots game but I will spare those who don’t enjoy the topic until the end of the post. For now, let’s dig into some current weather. The most interesting thing currently, at least for us, is the oddball wind today which apparently is due to our position in a low pressure trough. Summit wind today went from S to SSW then WSW and it looked as if it would trend through west before cranking up from the northwest. Instead, the wind shifted again to the S from WSW where it remained until around 2 pm when a Variable reading was recorded. Basically, a confused wind. Finally the 3pm observation is showing N. Essentially a quick 180 degree shift to the North. Incidentally, the wind was really, really light today allowing several inches of snow to lay around the mountain with more on tap through the night. The wind will rouse this snow and even some snowpocalypse snow onto its feet and whip it into wind slabs overnight. At this point, watch for trends with the wind direction and speed but right now my money is on a ideal loading speed until morning in the 50 mph range. Anticipate more snow as well as temperatures falling to -10F overnight. I think there will be a fair amount of snow available for building wind slabs so I would consider alternative plans to climbing in Huntington or skiing in Tucks tomorrow. And with a high tomorrow and Sunday of around minus 5F with winds near 100+ mph, I wouldn’t consider much more than a detour to treeline or a lap on the Sherburne before heading to the store for chicken wings and beer. Saturday night is expected to hit -15F so a full house will probably be warming up in the Harvard Cabin.

The Sherburne ski trail has really been a treat for folks this week and held onto all of the snowpocalypse snow. Today and tonight will freshen it up further. Remember that the Winter Lionhead Route is now open but it has seen limited traffic… expect delays due to heavy respiration rates. If you think professional football is stupid, stop reading.

Since Chris put me on the spot this morning in his advisory, I guess I have to make a pick for the victor of Number 49. It is likely to be a barnburner and I expect the Pats to have an inspired game if for no other reason than to silence the legion of haters out there. I don;t underestimate the Seahawks…it will be a real battle stopping Seattle’s running game, especially Wilson’s. If they keep Lynch contained, get a pick or two, the Pats might put them away by a couple touchdowns. The dynamic/brainiac duo of Brady and Belichick are undoubtedly fired up to find the loose thread that unravels the Legion of Boom, and I think they’ll find it. Pats 27, Seahawks 17.

Cheers and be safe out there this weekend!

-Frank