Posted 8:33a.m., Monday, February 07, 2011
Tuckerman Ravine has MODERATE avalanche danger today. Natural avalanches are unlikely and human-triggered avalanches are possible. The only exception to this rating is the Little Headwall which has LOW avalanche danger.
Huntington Ravine has LOW avalanche danger. Natural and human-triggered avalanches are unlikely.
While the summit is still in the fog this morning we’ve cleared enough to see how the mountain has changed following Saturday’s storm. High winds early in the day yesterday were able to strip much of the new snow out of the gullies in Huntington hence the Low rating. Pockets of windslab do exist in Huntington but they are isolated in nature and exist mainly in areas that were well sheltered from strong W and NW winds. Examples include the middle of Yale, below the ice in Central and the climber’s right side of the start zone for South Gully. Tuckerman is a very different story with little scouring and sculpting evident except for the upper reaches of Hillman’s and Left Gully. Evidence of avalanche activity can be picked out in many areas though additional loading has obscured many of the signs. As an example one can easily connect numerous pieces of a partially buried crown line across the Center Bowl and through the narrows of the Lip. This fracture is evidence of at least the second large avalanche in that forecast area this weekend, the first occurring Saturday morning shortly before 9 a.m.. The Observatory recorded blowing snow in their hourly observations up until about 9p.m. last night when winds dropped blow 45mph (72kph) and transport ended. Forecasted winds will stay below this threshold for the most part today with the occasional higher gust. A trace to 2” (5cm) of new snow is forecasted for later today but I don’t believe that it will play in as a major factor in today’s stability. More snow is expected to fall tonight and into tomorrow though it looks like it may only total a few inches. I would expect elevated avalanche danger tomorrow especially if the storm tracks closer to our area and we pick up more significant accumulation. Brian and I will be spending time in the field today trying to get a handle on where avalanche activity occurred, how the different slide paths have changed, and what role if any Saturday’s crust is playing in stability.
The John Sherburne Ski Trail has good coverage following the recent storms but the thundercrust from Saturday night’s wild weather makes for some tough turns. A handful of hearty souls made the most of it yesterday and acted like the Coast Guard cutters breaking up the frozen sea. It will only get better with each pass so do your public service and take a second lap!
- 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.
- This advisory expires at midnight. A new advisory will be issued tomorrow.
Justin Preisendorfer, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856