|Posted: 7:20 a.m., Thursday, April 22, 2010|
Tuckerman Ravine has Low avalanche danger today. Natural avalanches are very unlikely and human triggered avalanches are unlikely except in isolated pockets. Normal caution is advised.
A General Advisory is currently issued for Huntington Ravine. We are done issuing daily avalanche forecasts for Huntington for the remainder of the season. You will need to do your own snow stability assessments when using avalanche terrain in Huntington Ravine. A danger of falling ice exists and will persist until it all comes down.
Once again today’s weather is expected to deteriorate as the day progresses due to convective cells moving into the area. This scenario, as it transpired yesterday, is reminiscent of the classic mid-summer sunny start followed by building thunderheads in the afternoon. There is an increasing threat of rain as we move into the afternoon before it begins to clear out again tonight with the approaching high pressure for Friday. Slopes endured warm temperatures yesterday, particularly south facing aspects, as the sun peaked in and out of the clouds under light winds. Lower wind speeds allowed snow surface warming to climb rapidly during periods of sunshine only to drop again as dark clouds moved in and out of the higher summits. Expect snow left over from the weekend to be a sluffing concern today especially in locations that are still untouched by skiers and riders. If convective cells do develop the mountain may see a quick blast of water which has the potential to clean steep slopes of left over weekend snow causing loose snow avalanches. Not only will it be quite uncomfortable as thundershowers above treeline are usually pretty heavy and cold, but sluffing, if not managed well, could bring you into a crevasses or over cliff bands. Know where these hazards are and avoid them.
There are many existing crevasses around the mountain and the number is growing. The most prominent locations where crevasses are likely to be encountered are in the Lip and in the Headwall below the cliffs and ice. The Lip area has crevasses that encroach from both sides making it a poor choice for travel. Icefall potential will continue to rise today and you should be aware that there are still significant amounts of ice around the Ravine, with the largest being in the Sluice and Headwall. For this reason I would stay well away from Lunch Rocks. If you do decide to sit in this shooting gallery you need to be very vigilant to watch for icefall and plant yourself on the downhill side of a very large rock for protection. Have a plan in mind for when icefall does occur. Due to melting and undermining, there is no longer a route out of the Ravine. Plan to take off your skis or board and walk down to Hermit Lake where you can rejoin the Sherburne for the trip downhill. Other areas, such as Hillman’s Highway, also have undermined snow but recent snow has obscured some of the open holes. Use caution around rocks, holes and sagging areas of snow. And lastly, lots of rocks have begun to melt out from the lower and middle sections of popular runs and there are numerous pieces of ice littering the floor of the Ravine. Take a good look at what will be in your runout before dropping into any line.
The Lion Head Winter Route is open. The upper two thirds of the John Sherburne is open with big bumps and thin cover. The bottom third is closed so cross over to the hiking trail when you come to the rope. To stay out of the mud and help prevent erosion please do not walk on the closed ski trail. For the safety of those hiking up the Tuckerman Ravine trail from Pinkham do not ski on the hiking trail.
Christopher Joosen, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856