Avalanche Advisory for Tuckerman and Huntington Ravines

Posted: 8:24a.m., Friday, May 14, 2010

Tuckerman Ravine has Low avalanche danger. Natural avalanches are very unlikely and human triggered avalanches are unlikely except in isolated pockets. Normal caution is advised. A General Advisory is currently issued for Huntington Ravine. We are done issuing daily avalanche forecasts for Huntington for the remainder of the season. You will need to do your own snow stability assessments when using avalanche terrain.

Early this morning a drop in wind speed associated with a shift in direction began a period of light snow and freezing fog for the higher summits. Sporadic precipitation should continue and turn to all rain quickly as temperatures climb above freezing towards 40F (4.5C). Wind velocities will build into the 70mph (112kph) range by late in the day as a prelude to the cold front coming our way behind the warm front we’re dealing with this morning. Convective cell potential exists for the afternoon bringing a possible thunderstorm in addition to today’s rain. Temperatures will drop tonight into the 20’s (-3/-4C) which will bring the return of snow and mixed precipitation types through the dark hours into the beginning of the weekend. A wintry mix should prevail with the summit mercury climbing to the freezing mark on Saturday with peak winds around 70 mph (112kph) in the morning dropping to 35-40mph (56-64kph) later in the day. We’ll have more on Saturday’s weather in our weekend update this afternoon. We continue to struggle with some technical problems with our website that began a week ago but we should have this posted by early afternoon.

Available snow for skiing enjoyment gets a little smaller day by day, but the diehard mountain slider will still find something to ski or ride if they just can’t put the boards away yet for the summer. You’ll need to balance the amount of turns with the building hazards in your fall line. These usual springtime hazards should be on the backcountry traveler’s watchlist today. It’s especially important at this time of year to hike up what you plan to ski down so you can assess the conditions before dropping in on top of them. The biggest issues you’ll be facing are CREVASSES, UNDERMINED SNOW, and FALLING ICE. As the snowpack deteriorates and gravity pulls it downhill it rips and tears apart leaving cracks and chasms of varying sizes. Some are only big enough to grab a ski or board while others could eat you and your entire group in one quick gulp. Please don’t feed the crevasses it only gives them bad habits. By definition you won’t see the undermining that has taken place beneath the snow, but you can be on the lookout for clues to the worst locations. Sagging snow, open holes with running water, and “moats” near rocks are all indicators of undermining. Avoid these areas and stay on top of the snow. Although trailing a bit behind crevasses and undermining as the main concern icefall will continue to be an issue of concern. Massive amounts of ice have already succumbed to gravity and fallen from the walls to the floor of the Ravine. Some additional pieces of ice remain in all areas waiting for warmer temperatures to join its family in the floor. Keep your eyes and ears open for this hazard and have a plan in mind should icefall occur.

The Tuckerman Ravine Trail is CLOSED TO ALL USE from Lunch Rocks to the junction with the Alpine Garden Trail. This includes the Lip area and the section of the hiking trail from the floor of the Ravine through the top of the Headwall. Only this section of the trail is closed, and it includes the Lip. This annual closure is due to the magnitude of crevasses and undermining that develop in this area during the spring melt-out. A fall in this area would have severe consequences. The Lion Head Summer Trail is open and provides an alternate route to the summit.

Please Remember:
Natural events such as avalanches are impossible to accurately predict in every instance. This Advisory is one tool to help you make your own decisions in avalanche terrain. It should be used along with safe travel techniques, snow stability assessments, an understanding of weather’s effect on the snowpack, and proficiency in avalanche rescue.
You should obtain the latest weather forecast before heading into the mountains. Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast.
For more information, contact the U.S. Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center or Hermit Lake Shelters or the HMC caretaker at the Harvard Cabin. A new avalanche advisory will be issued tomorrow and this advisory expires at midnight.

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