Avalanche Advisory for Thursday, May 2nd, 2013

This advisory expires tonight at 12:00 midnight.

Tuckerman Ravine has Low avalanche dangerNatural and human triggered avalanches are unlikely. Huntington Ravine is not posted. We are no longer monitoring conditions in Huntington this season. You will need to do your own snow stability assessments. A danger of falling ice exists and will persist until it all comes down.

Yesterday was likely the warmest day at Hermit Lake this season, hitting about 62 degrees F in the afternoon!  This morning we have an inversion on the mountain with the summit at 44F  while the base sits at 41F.  Sandwiched between these, at the mid elevations, is even warmer air, according to sensors on the Auto road.  The Ravines seem to be hovering around 50F if you average the temperatures from the 3800, 4000, and 4300 foot levels.  Therefore, snow surfaces will start out soft and should remain that way even though a back door cold front is heading our way, likely to move in this afternoon.  This will bring clouds to the summits and probably a little rain, so as always bring some rain gear.  As I discussed yesterday the greatest concern continues to be the lack of freezing temperatures and the weakening of ice that remains across the Ravines.  The vast majority of this annual threat still remains and has been above the freezing  level for almost 6 days in a row.  Because of this we are very aware that we are currently in a high potential icefall period.

Objective mountain hazards should be figured prominently into your travel plans today. These include:

1. POTENTIAL FOR FALLING ICE. I mentioned it already but it’s worth stating again that icefall leads as the main issue to be aware of in the Ravine.  Over the years many people have been severely injured or killed by icefall in Tuckerman, while countless others have had close calls. Minimize the time you spend in high risk areas where ice may fall from above you, such as under the Headwall or at Lunch Rocks. DESPITE ITS POPULARITY, LUNCH ROCKS IS NOT A SAFE PLACE TO SIT AND WATCH THE ACTION.  Sitting on the Left/South side of the Ravine will reduce your risk.   

2. CREVASSES AND WATERFALL HOLES. The best way to avoid this hazard is to know where the holes are located, and avoid these areas. You can do this by climbing up what you plan to descend. The most prominent area where crevasses have become a serious threat is in the Lip and Center Bowl. Falling into one of these holes or breaking through a weak snow bridge could be fatal for you or someone in your group.

3. UNDERMINED SNOW. As the snowpack continues to get thinner, we are starting to see this problem emerge. Many gullies have running water in them, which melts away the snow from below. While it may look thick and strong on top, you don’t really know until you step through. The consequences could range from minor annoyance to being swept into an icy water channel. If you see a small hole in the snow, realize it’s larger beneath the surface. A common practice is to probe the depth of snow to help locate problem areas.  It’s another good reason to carry a collapsible avalanche probe.

The Sherburne Ski Trail is closed one third the way down from Hermit Lake at crossover #7. At the rope, you need to cross over to the hiking trail and walk down to the parking lot. Do not walk or attempt to ski down this muddy trail below the rope.

The Lion Head Winter Route remains open and offers the most direct access to the summit of Mt. Washington from the east. This is a very steep route and is often more challenging in spring conditions. An ice axe and crampons are highly recommended for this route. The Lion Head summer trail is still closed. Other routes exist and might be good options with weather like today, but realize summer trails are still deeply buried under snowfields of snow.  All routes still need mountaineering equipment to safely travel on them.

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 or the AMC at Pinkham Notch Visitor Center or Hermit Lake Shelters.
  • Posted at 6:400 a.m., May 2, 2013. A new advisory will be issued tomorrow.

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

2013-05-02 Print Friendly