Avalanche Advisory for Wednesday, 4-18-2012

This advisory expires at midnight, Wednesday 4-18-2012

Tuckerman Ravine has Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.  Expect the possibility of wet point releases/sluffing induced by human travelers and icefall triggers. Huntington Ravine is under a General Advisory. You will need to do your own snow stability assessments when using avalanche terrain in Huntington. A danger of falling ice exists, and will persist until it all comes down.

The summer like heat will abate a bit, but nice weather will continue over the next couple of days.  Currently Friday appears to begin a several day period of some much needed moisture, but more on that tomorrow.  The last 48 hours of high temperatures have generated some impressive results on the mountain, albeit negative from a skier’s perspective.  We have lost a lot of the gains we made from the early April snow and are back into deterioration mode.  Rocks and crevasses are jumping out all over the place, particularly in areas that were thin to begin with only a veneer of new snow.  As is usually the case we are coming closer to average concerning snow coverage and timing, but I would say we are still a bit behind. That being said there is still enjoyment to be had with skis and boards, however realize timing and hazard recognition is everything.  Lower risk from objective mountain hazards (icefall, crevasses, avalanches) exist on the left or southern side of the Ravine than on the right so staying to the Left Gully side of the Ravine is our recommendation.  Choosing our recommendation does not completely eliminate the hazards described below, but dramatically reduces your expose to them.

Icefall has been occurring from the Headwall, Sluice, and other areas. Many people have been injured or killed through the years by falling ice and a number of people had some very close calls this week. Icefall has been rapidly increasing this week due to the heat and the extended weather forecasts looks like this will continue. The greatest icefall hazard exists from the Center Headwall and the Sluice ice above Lunch Rocks, but there is potential for this to happen in just about all of the gullies.  Sitting at Lunch Rocks may be traditional, but it’s right in the cross-hairs of significant ice shelling from multiple directions.  Most of our icefall tragedies have happened at Lunch Rocks (Icefall Rocks) so they should be avoided as your base camp.   You should always be looking uphill and thinking about what might fall from above…ice, avalanches, dropped snowboards, people without crampons, etc. can quickly turn a great day into a disaster.

The Center Bowl and Lip areas have numerous deep crevasses, undermined snow, and waterfall holes. Because the consequences of falling into one of these crevasses are severe we recommend avoiding this area entirely. There are smaller crevasses outside of the Lip and Center Bowl area.  As an example underneath the Sluice ice is an area where we’ve historically seen dangerous undermined snow and crevasse hazard. Hillman’s Highway is yet another area where undermined snow can be found.

Hikers should not plan to use the Tuckerman Ravine Trail to climb to or descend from the alpine zone and the summit of Mt. Washington. From Pinkham, Lion Head, followed by the longer Boott Spur, are much better options. The heat has devoured snow on the John Sherburne Ski Trail.  It has been amazing to see the melt rate due to record warmth eating coverage all the way to Hermit Lake.  The ski trail is now closed to all use.  Avoid mud over your boot tops and eroding the trail by walking down to Pinkham Notch from Hermit Lake on the Tuckerman Ravine hiking trail.

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, the caretaker at Hermit Lake Shelters. A new advisory will be issued tomorrow.

Christopher Joosen, Snow Ranger
USDA Forest Service, White Mountain National Forest

4-18-2012 Print Version