Current Avalanche Advisory
   Issued January 31, 2006

   Good morning, this is Sue Burak with an avalanche information advisory
   for Tuesday January 31, 2006.

   MOUNTAIN WEATHER

   Today's temperatures will warm to the mid to upper 30's today at the
   8,000 ft. Winds will be light from the west and northwest as a flat
   ridge builds today. Expect daytime highs to reach the mid 50's by
   Wednesday and Thursday.

   OUTLOOK

   New snowfall totals range from 2 inches at Rock Creek to 5 inches at
   the sensor on Tioga Pass. Mammoth Pass picked up 0.5 inches of water.

   An impressive plume of precipitable water is aimed at the Central
   Sierra on Wednesday. However, very
   little precipitation is expected east of Sierra Crest and QPF
   forecasts are for 0.5 inches in Mono County and 0.25 inches for
   northern Inyo County. The best chance of precipitation will be
   Wednesday night as models show the moisture plume sagging south. The
   next shortwave will reach our area Saturday and will bring more wind
   than snow. At this point, models suggest next week will be dry.

   SNOWPACK AND AVALANCHE DISCUSSION

   With yesterday's wind and snow, wind loading is the main forecasting
   concern. Wind speeds greater than 10 miles per hour are sufficient to
   move cold new snow. Winds greater than 22 miles per hour are required
   to move higher density surface snow. I observed several recent slab
   avalanches after Saturday's storm on the southeastern aspects of the
   Dana Plateau.

   I also observed my first firnspiegel of the season on southern
   aspects. Firnspiegel is a thin sheet of ice formed by rapid refreezing
   of solar-heated snow. By February, sun angles are increasing and the
   snow surface is receiving greater amounts of solar radiation than they
   did in December and the first part of January. Solar radiation  melts
   snow, not the air temperature. Southern aspects in many parts of the
   forecast area have well-bonded melt freeze layers on the surface, with
   a faceted snowpack below. These slopes will become a forecasting
   concern as the season progresses.

   There is a variety pack of snow surface conditions in the forecast
   area. There are ice crusts on south facing slopes, wind hammered snow
   above treeline, and faceted snow and surface hoar at or below
   treeline. Shallow wind slabs have formed on the lee side of
   ridgelines, primarily from southwest winds. Watch for cracking and
   collapsing of these slabs on steeper slopes. Look for small cornices
   that could have formed in the last few storms.

   Today, a MODERATE avalanche danger exists on recently wind-loaded
   slopes steeper than 35 degrees. The avalanche danger on non wind
   loaded slopes remains LOW.


   Please note that the avalanche danger rating in this advisory expires
   in 24 hours. This advisory is our best interpretation of snow pack
   conditions and NWS forecasts issued today.

   Avalanches do not happen by accident and most human involvement is a
   matter of choice, not chance. Most avalanche accidents are caused by slab
   avalanches that are triggered by the victim or member of the victim's
   party. Even small slides can be dangerous. Always practice route
   finding skills and carry avalanche rescue gear. Remember that
   avalanche danger ratings are only general guidelines. Distinctions
   between geographic areas, elevations, slope aspects and slope angles
   should be made.