Avalanche Advisory for Monday, April 14, 2014

This advisory expires at 12:00 midnight.

Tuckerman Ravine has Low avalanche danger. Natural and human triggered avalanches are unlikely. Huntington Ravine is under a General Advisory. You will need to do your own snow stability assessments when traveling in avalanche terrain in Huntington. A danger of falling ice exists, and will persist until it all comes down.

AVALANCHE PROBLEM: The Low avalanche danger today is a result of multiple days of warm weather and cold nighttime temperatures. This diurnal cycle adds a lot of strength to the snow surfaces and reduces the potential for avalanche activity to a point where we are comfortable calling the danger level “Low.” Understand that predicting avalanches is not a perfect science. With this in mind, when traveling in avalanche terrain we always recommend carrying avalanche rescue equipment, practicing safe travel rituals, and keeping your awareness up for situations that could increase your risk.

WEATHER: If you’ve had any doubts about whether spring would ever arrive, today should be enough to erase them thoroughly. Valley temperatures may hit 70°F. The temperature sensors along the Auto Rd are already reading over 50°F at the 4300’ elevation! Higher summits forecasts for today call for the mountains to be in the clouds, but currently this is not the case. Even so, you should be ready for visibility to decrease if the cloud levels drop during the day.

Yesterday we received a surprise of about 2” of new snow at Hermit Lake before precipitation turned over to ice pellets and rain. At this point in the season, we will take whatever we can get to keep the existing snowpack fresh. It also highlights the ability of mountain weather to be somewhat unpredictable, so it’s best to be prepared for poor weather even if forecasts look promising.

SNOWPACK: We are certainly into a springtime snowpack. The ravines have spent far more time above freezing than they have below freezing over the last 24 hours. Today you should be expecting all surfaces to soften with the intense warming. Some slopes may turn into deep and unsupportive slop as well. Melt water may find its way to lower layers in the snow and produce a wet slab avalanche. My thoughts are that this will be more of a problem with Tuesday’s rain than with only melt water today.

OTHER HAZARDS: We are at the beginning of the icefall season, which means that there is a lot of ammunition perched high on the cliffs of the ravines. Sitting at Lunch Rocks is a lot like looking down the barrel of a loaded gun. You don’t want to be there when heat and sunshine pull the trigger. Other springtime hazards, such as undermined snow and crevasses, are emerging as well. If you’re planning a future trip to the ravine, do your homework about these issues in advance!

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.
  • Posted 7:45 a.m. 4-14-2014. 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

2014-04-14 printable