Good morning, this is Sue Burak with the Eastern Sierra Avalanche
   Center with an avalanche advisory posted for Saturday April 12, 2008.

   The Tuolumne Rangers report the Tioga road (Highway 120) has melted out
   from the road closure gate outside of Lee Vining up to the Warren Fork
   of Lee Vining Creek, with patches of snow from Warren Fork up to Ellery
   Lake. Skiers coming in from the east side should be prepared to walk
   the first 4-5 miles of road above the gate before you hit the good snow
   near Ellery Lake. Skiers coming up the Snow Creek trail from the west
   side report that the snow line begins just above the top of the
   switchbacks; everything below that level has melted out.

   MOUNTAIN WEATHER

   Morning temperatures are 10 degrees F higher today than yesterday. The
   top of Mammoth Mountain was 31 F at 6 AM. For today, winds will be
   light with highs approaching 55 F at 9,000 ft. Higher elevations could
   see highs near 50F. Night time low temperatures may reach the freezing
   temperature at most locations.

   The unusually strong high pressure ridge continues to build over the
   area today. Southeast winds are expected at the higher elevations above
   10,000 ft. Another few degrees of warming is expected with highs
   ranging from 44 to 54 above 10,000 ft.

   Just when we thought spring had arrived, the National Weather Service
   issued a special weather statement yesterday alerting us to a
   significant pattern change by Monday. On Monday, gusty winds will
   increase ahead of an approaching cold front with high wind warnings
   expected. Tuesday and Wednesdays temperatures are expected to fall by
   20 F from Saturday and Sundays afternoon highs. There is a chance for a
   few snow showers on Tuesday and Wednesday.

   SNOWPACK AND AVALANCHE DISCUSSION

   The well advertised warm up is in progress. The warmest mountain
   temperature yesterday was at Mammoth Pass, 9,400 ft with a high of 58F.
   Main Lodge hit 52F at 5 PM. Leavitt Lake and Gem Pass at 10,700 ft saw
   5-6 degrees of warming with highs of 49F. Otherwise Tioga Pass, Ellery
   Lake and Slide Canyon saw a degree or two of warming yesterday but were
   still 10 degrees warmer than Wednesday.

   Morning temperatures are 10 degrees warmer with some stations barely
   reaching freezing this morning. Leavitt Lake and Mammoth Pass, both
   around 9,500 ft, had one hour of freezing temperatures this morning.
   Bishop Pass at 11,400 ft just hit freezing temperatures at 5 AM this
   morning. Other high elevation sensors show lows around in lower to mid
   20s, indicating a good solid freeze last night.

   Despite highs in the 40s yesterday, it was clear that the suns energy
   was melting the snow, not the air temperature. Where we were traveling,
   the snow was soft at 9 AM at 11,000 ft. Despite the evaporating effect
   from light winds, the snow was over the boot top on a southern aspect.
   There is a spring snow conditions right with heavy wet winter snow on
   north aspects at elevations above 10,000 ft. Watch out for this type of
   snow today because on steep slopes, it will readily slide with a
   trigger once the sun melts the surface.

   High elevation southern aspects, especially collection zones like bowls
   have a mixture of wet patterned snow and wind drifted wet winter snow.
   This snow was blown in from last weeks parade of windy dry storms. The
   only true granular corn snow was found on lower angle terrain in the
   area we were traveling through. By mid day, traveling is pretty slushy
   on all treeline slopes to mountain tops on SE-S and SW aspects.

   As long as nights remain cold with a good freeze, avalanche activity
   will probably be confined to surface point releases, though these can
   get large and step down to some of the ice lenses and unconsolidated
   faceted snow lower in the snowpack.

   Well shaded, high elevation slopes are beginning to thaw and fine
   grained winter snow will be warming for the first time this season.
   Start early and get off all slopes by noon, especially steep southerly
   aspects. Pay particular attention to traveling under rock ridges or in
   narrow canyons and gullies that could become a terrain trap.

   BOTTOM LINE
   For today, the avalanche danger rating is LOW this morning, rising to
   MODERATE on all slopes and aspects by noon.

   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. Backcountry travelers should
   be aware that elevation and geographic distinctions are approximate and
   that a transition zone exists between upper and lower elevations.

   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 of 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.