8:14 a.m., Saturday, November 23, 2002

   This is a U.S. 5 Scale Danger Rating Avalanche Advisory for Tuckerman
   and Huntington Ravines. We will likely go back and forth between
   General Advisories and 5 scale ratings until we need to go to a daily
   bulletin. If a 5 scale bulletin is issued it expires at midnight on
   the day of issue and you can expect another bulletin the following
   morning. When a General Advisory is posted another bulletin may or may
   not be issued the following day depending on conditions. Climbers
   heading into Huntington should check the avalanche bulletin before
   leaving Pinkham Notch or Hermit Lake each morning. Until the Harvard
   Cabin opens on December 1st the avalanche bulletin will not be posted
   there due to no campers being there overnight.

   A tight pressure gradient should generate winds over 100 mph today on
   the higher summits making for Blizzard conditions with temperatures
   dropping into the singles. High winds are expected for the valleys as
   well with some models producing gusts upward of 50 mph. Be prepared
   for full winter arctic conditions above treeline today. Due to
   blizzard conditions and low visibility you may want to ask why? Why go
   out when the hot tub has just got up to temperature? Play it
   conservative today, it will be an easy day to get lost.

   Tuckerman and Huntington Ravines will move toward CONSIDERABLE
   avalanche danger today. Natural avalanches are possible and human
   triggered avalanches are probable. Be increasingly cautious in steeper
   terrain. Over the past 24 hours the summit of Mount Washington
   received 2.1 inches of snow and is forecasted to pick up another 6 or
   more today. The big factor today beside more precipitation is wind. As
   one system moves out to the Maritimes high winds will move into the
   area on a Northwesterly flow. Currently winds are 40 mph from the NW
   and increasing. As they increase they should load new snow into lee
   areas of the Ravines. Loading should intensify through the day
   culminating with the probability of hard slabs over lower density
   slabs this afternoon as high winds batter crystals into small snow
   grains. Small grains and high winds usually pack into dense hard
   slabs. Dense slabs over a softer slab is a classic instability
   scenario. Another factor to watch is the potential near surface
   faceting of crystals over the next few days. Hermit Lake picked up .75
   inches of rain before the snow which brought with it latent heat into
   the snowpack. This is now be covered with cold snow and an ambient air
   temperature moving toward the single digits F. This temperature
   gradient and plently of moisture in the snowpack may show some
   intresting crystal growth. We'll wait and see. So areas of most
   concern are those that already had significant existing snowfields
   before this storm. These pockets offer new snow a bed surface to
   avalanche on compared to brush or rock dominated areas. The largest
   areas are still in Tuckerman Ravine. Left Gully, the Chute, and areas
   North towards the Sluice do have sizeable snowfields. Isolated patches
   in the Huntington Gullies also offer good potential bed surfaces.
   Remember if the snowfield is large enough to ski or recreate on it's
   large enough to avalanche.

   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.

   Pull out your beacon and practice, ONLY YOU CAN SAVE YOUR PARTNER!!
   Review your safe travel rules, techniques for assessing snow
   stability, and sign up for an avalanche course. We have all the
   avalanche courses offered in the valley this winter on our website,
   csac.org.

   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