Posted: Wednesday, January 12, 2011 8:45 a.m.
Tuckerman Ravine: The Center Bowl, Lip, Sluice, Right Gully and Lobster Claw have HIGH avalanche danger. Natural avalanches are likely and human-triggered avalanches are very likely. Travel in avalanche terrain is not recommended. All other forecast areas in Tuckerman have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely.
Huntington Ravine: Central, Yale, Damnation and North Gullies have HIGH avalanche danger. Natural avalanches are likely and human-triggered avalanches are very likely. Travel in avalanche terrain is not recommended. All other forecast areas in Huntington have Considerable avalanche danger. Natural avalanches are possible and human-triggered avalanches are likely.
Finally a storm is upon us! We’re grateful even if it’s one that we would have taken for granted in past years as just another expected weekly event. The Nor’easter hammering coastal areas should pick up its intensity in the mountains as the day progresses. The higher summits of the Presidential Range are expecting 5-7” (13-18cm) of snow today with another 1-3”(2.5-7.5cm) tonight and maybe even a little more tomorrow. This is a bit colder of a Nor’easter than usual and summit temperatures will be around 5F (-15C) today, drop to 0F (-18C) tonight and then re-bound a bit tomorrow into the upper singles (F). This translates into expectations for lower density snow which will make for easy transport and cold slab development. Wind speeds will ramp up from the current 43mph(69kph) and push over 70mph(113kph) later today while they shift from the E to the N. Anticipate this to cross-load S and N facing aspects during the first part of the day before directly loading S-facing slopes and cross-loading E aspects later this afternoon. Avalanche danger will increase through the day taking most of the morning and early afternoon to reach the forecasts of High and Considerable.
Although certain forecast areas have not been posted at High remember Considerable is a substantial rating in its own right with natural avalanches being possible and human triggered avalanches being likely. This is complicated by forecast areas in Tuckerman and Huntington Ravines being very close together, particularly the former. As you transition from the Sluice, to the Lip, over to the Center Bowl and the Chute the aspects change, but their proximity allows avalanches to propagate into one another including criss-crossing run out paths. As an example the Center Bowl is posted at High because we have concern a fracture in the Lip could propagate into the Bowl partially due to the cold elastic nature of expected slabs today. However, just next to the Center Bowl is the Chute, posted at Considerable, which should receive less loading today but still contain formidable problems. To access this area you would generally need to travel under other paths that are forecasted with High avalanche danger today. The avalanche cycle of a couple days ago has filled in a lot of the Tuckerman floor so we expect avalanches to travel much farther than a week ago. Once you pass the Connection First Aid Cache just before the ravine floor you are in avalanche terrain.
This storm will reinvigorate the Sherburne Ski Trail but realize that before this storm most of the trail was ice and vegetation. It’s not time to put away the rock skis yet!
- 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