8:34 a.m., Sunday, December 29, 2002

   Tuckerman Ravine has Low and Moderate Avalanche Danger. Left Gully,
   Hillmans Highway, the Lower Snowfields, and the Little Headwall have
   Low avalanche danger. Natural avalanches are very unlikely and human
   triggered avalanches are unlikely except in isolated pockets on steep
   snow covered open slopes and gullies. Normal caution is advised. Right
   Gully, the Bowl, the Headwall, and the Lip have Moderate avalanche
   danger. Natural avalanches are unlikely and human triggered avalanches
   are POSSIBLE. Use caution in steeper terrain.

   Huntington Ravine has Low Avalanche Danger. Natural avalanches are
   very unlikely and human triggered avalanches are unlikely except in
   isolated pockets. Normal caution is advised.

   The summit picked up an inch (2.5 cm) of new snow since 10 pm last
   night with another half an inch (1.25 cm) expected before clearing
   skies around noon. Snow has been falling with WNW winds between 35 and
   60 mph (55-95 kph) which is close to ideal for new loading into the
   ravines. Although an inch with perhaps another inch coming isn't much,
   it can be quite suprising how much new slab can become deposited with
   light densities and ideal winds. New snow densities on the summit is
   running around 6%. This light snow with moderate WNW winds, which will
   be increasing through the day, will load E and SE aspects and cross
   load others. So areas like the 'Lip' which just came down from
   Considerable will be trending back to that rating as the morning
   progresses. Expect this increasing avalanche danger to trend toward
   the next higher rating as the morning continues. "Low" areas will be
   heading towards "Moderate" and "Moderate" areas towards the upper end
   of the rating pushing "Considerable". During field observations
   yesterday we found a real mixed bag in both snow conditions and
   stability. This has been the main reason the rating has been a bit
   slow to come down over the past couple of days. We have had enough
   unstable areas under the Headwall, in the Lip, Sluice, and Right gully
   to not quite qualify as Low's "isolated pockets". We found some sun
   crust, soft slab, hard slab, and very hard slab or what we call
   "windpack". Stability seemed to change every 20 meters. One item which
   isn't much of a concern is yesterday's surface hoar discussion. The
   little we had was taken care of by wind in almost all areas. In hasty
   pits we found variable stability, but one theme was fairly consistant.
   We found hard slab over a very thin 1 mm layer of what appeared to be
   intact unconsolidated plates and stellar crystals. The layer was so
   thin it was difficult to ascertain the true weakness. However this was
   bridged by a thick pencil to 1 finger hard slab which offered a great
   deal of tensile strength. Slab thickness varied widely but was 45 cm
   and greater in most places. I believe that if avalanche activity from
   the new snow ran over these areas of hard slab it may step down to
   this weakness. It will take a fair amount of force to trigger these
   areas of hard slab, but it is possible for an aggresive skier or rider
   to find a weak trigger point causing slope failure. In areas posted at
   Low, there are isolated pockets of instablity so stay on old surface
   when possible. One example of these pockets is the top center of the
   start zone in Left Gully near the horizon. Some of these pockets may
   also be found in unusual places due to the very high winds on Thursday
   such as low in Huntington Ravine. So use caution on the approach to
   climbs. We currently have quite variable snow stability conditions.
   You may find yourself going through different areas of stability very
   quickly so keep your snow stability skills on high alert. Also
   anticipate the possibility of an increasing avalanche danger with
   continued snow showers forecasted this morning.

   AS ALWAYS, THIS ADVISORY IS ONE MORE TOOL TO HELP YOU MAKE YOUR OWN
   DECISIONS IN AVALANCHE TERRAIN. It should be used along with your own
   snow stability assessments, knowledge of safe travel techniques, skill
   in mountain weather's effect on the snowpack, and avalanche rescue.

   THE WINTER LION HEAD ROUTE IS OPEN. THE ROUTE LEAVES FROM THE
   HUNTINGTON FIRE ROAD AND HAS ORANGE SIGNS STARTING ON THE TUCKERMAN
   RAVINE TRAIL AT ROUGHLY THE 1.8 MILE MARK. IT IS A STEEP AND
   CHALLENGING ROUTE. CRAMPONS, AN ICE AXE, AND THE ABILITY TO USE THEM
   WITH SKILL ARE REQUIRED FOR SAFE TRAVEL.

   The John Sherburne ski trail is coming along slowly and improving.
   However, waterbars, rocks, brush and patches of water ice are hiding
   just under the new snow.

   PLEASE REMEMBER:

   o Any new precipitation may increase the avalanche danger, this
   includes wind transported snow.

   o Obtain latest weather forecast before starting out.

   o For more information, contact the U.S. Forest Service Snow Rangers:
   AMC at Pinkham Notch Visitor Center or Hermit Lake Shelters.

   o This avalanche bulletin will expire at midnight.

   Christopher Joosen, Snow Ranger
   USDA Forest Service
   White Mountain National Forest