Tuckerman Ravine has EXTREME and HIGH avalanche danger. The Lobster Claw, Right Gully, the Sluice, Lip, Center Bowl, and the Chute have Extreme avalanche danger. Avalanches are certain. Avalanche terrain, which includes run out paths, should be avoided. Left Gully, Hillmans Highway, and the Lower Snowfields have High avalanche danger where natural avalanches are likely and human triggered avalanches are very likely. Travel in avalanche terrain is not recommended.
Huntington Ravine has EXTREME and HIGH avalanche danger. North, Damnation, Yale, and Central Gully have Extreme avalanche danger. Avalanches are certain. Avalanche terrain, which includes run out paths, should be avoided. Pinnacle, Odell, South, and the Escape Hatch have High avalanche danger where natural avalanches are likely and human triggered avalanches are very likely. Travel in avalanche terrain is not recommended.
It is important to note that in some cases the runout paths of areas posted at Extreme cross the approaches to areas posted at High. The differences in ratings reflect that south facing aspects will see very intense loading which will generate more avalanche cycles than areas posted at High. It is clear however that High areas will likely see natural avalanches today. Whether the travel advice is “should be avoided” or “not recommended” the message is clear, give all avalanche terrain a wide berth and leave the Ravines alone today.
The summit and Hermit Lake have both picked up about 20” (50cm) so far with several more inches expected today. Winds are slowly shifting from the NE to the N and increasing with gusts expected to reach 110mph later this morning. Avalanche terrain in both Ravines will probably see peak instability around lunch time, but we anticipate widespread avalanches through the day. As winds scream at their maximum velocity I expect some areas to see some scouring, but I also believe some strong lee areas will see the building of enormous whales of snow in multiple start zones. Slopes that face the south will become the most transformed from this event and we look forward to seeing what nature’s forces will do in these areas. Winds will shift again tonight and tomorrow from the N to the NW which will begin another loading event so expected more elevated danger ratings tomorrow.
Although we do not avalanche forecast for other Ravines, Gulf, trails, or routes you can expect snow instability in many steep mountain locations resulting in avalanche concerns. An example is the generally thin Lion Head Winter Route. Steep pockets in the trees and areas at treeline should be suspected to harbor instabilities. Other examples can be found in locations above, at, and below treeline. No matter where you are this weekend keep avalanches on the brain. REMEMBER, UNUSUAL WEATHER CREATES UNUSAL AVALANCHES.
The Sherburne will begin a bit slow due to deep snow. As it gets travelled it will keep getting better. Expect high winds today to create some deep drifts and whales. He has been waiting to return to his former glory and Johnny’s back! A true adventure should be had by willing skiers and riders.
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.Posted 8:45am 02-09-2013. 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