Expires at Midnight 1-13-2012
Tuckerman and Huntington Ravines have HIGH avalanche danger today. Natural avalanches are likely and human triggered avalanches are very likely. Travel in avalanche terrain is not recommended due to very dangerous avalanche conditions. Some areas are not yet posted due to the overall lack of snow. These include the Lobster Claw, the Lower Snowfields, and the Little Headwall in Tuckerman and the Escape Hatch in Huntington. Forecasts for these locations will begin when conditions warrant.
The Snow Rangers are happy again due to yesterday’s snow, snow overnight, and snow today. We are currently coming to the tail end of one system and getting ready for another snow shot from another, with an additional 3-5” (7.5-12.5cm) forecasted for today. This is in addition to the 6.7” (17cm) the summit received as of midnight and snow every hour since that collection. Quite plausibly, we could end up with about a foot (30cm) of snow in the previous 36 hours by dinner time today. Snow was brought in on winds mostly from the E, which was a bit off from the expected SE, on Thursday and very early this morning. This crossloaded a number of aspects that face towards the S and N. This includes areas in Right Gully, Left Gully, and Hillman’s Highway in Tuckerman and North, Damnation, Yale, and South Gullies in Huntington. Notice we added Right Gully to the daily forecasts today. We have not see it since this storm commenced, but due to historical knowledge, the crossloading it received yesterday, and what it will receive today it has enough bed surface area and diminishing anchors to harbor avalanche potential.
Over the past couple of hours winds have walked rather quickly from the E over to the SW and then back a little towards the S. A directional trend towards the W will take over this morning which will start moving yesterday’s snow in the more typical direction, directly into the Ravines. Winds will move to the WNW late today and come from the NW by morning. Thursday’s storm snow on the ground above treeline and new snow falling today will be delivered on increasing velocities moving from a current around 40 mph (64kph) to over 70 (112kph) this afternoon. These are ideal conditions to create new unstable slabs and natural avalanche activity. The wind speed ramp up will generate denser harder slabs over a bit lighter early slabs that developed on lower wind speeds. Some bulls-eye points and key issues to remember today:
- We are on an increasing avalanche trend with rapid developing instabilities this afternoon as winds increase from the W to 70+mph.
- Winds will pick up snow on the ground above treeline and mix it with new snow, forecasted between 3-5”, moving a high volume of snow into both Ravines.
- Expect very low visibility in the Ravines and above treeline.
- Travel in avalanche terrain is not recommended due to very dangerous avalanche conditions.
The other big news is the front that will be moving into the Mount Washington region after dark producing winds gusting as high as 110 mph (176kph) and dropping the mercury like a rock getting into the -5F (-21C) area. These extreme wind speeds will move a tremendous volume of snow into the lee east facing flanks of Washington. Likely causing some avalanche cycles overnight and producing a wide amount of variability in snow conditions tomorrow. Expect slopes and gullies to be both scoured as well as loaded depending on locale by daylight on Saturday morning. Tomorrow winds will subside, but we could see the coldest air of the season staying firmly in the negative numbers for the weekend. Many excited mountaineers and mountain travelers are coming to the hills for the long holiday weekend. If you’re one of them be prepared with excellent winter clothing and skills. The most common issues we see are inadequate footwear, mitts, head, and face protection.
Be sure to check back for the most recent avalanche advisory Saturday morning and read our Weekend Update that will be posted early tonight at www.mountwashingtonavalanchecenter.org
- 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 8:35a.m. Month Year. 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