314 
 WTNT41 KNHC 100942
 TCDAT1
 TROPICAL STORM OPHELIA DISCUSSION NUMBER  16...CORRECTED
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 5 AM EDT SAT SEP 10 2005
 
 ...CORRECTED 72 HOUR INTENSITY...85 KT...IN TABLE...
  
 RECON REPORTS THROUGH 06Z LOCATED THE CENTER WITHIN A LONE BURST OF
 DEEP CONVECTION THAT HAS BEEN ROTATING SOMEWHAT WITHIN A LARGER
 MID-LEVEL CIRCULATION...WHICH IS STILL MOVING GENERALLY
 NORTHEASTWARD.  THE MINIMUM CENTRAL PRESSURE MEASUREMENTS BY
 DROPSONDE WERE 983-985 MB... BUT MAXIMUM 850 MB FLIGHT LEVEL WINDS
 WERE 70 KT...CORRESPONDING TO ABOUT 56 KT AT THE SURFACE.  DVORAK
 T-NUMBERS HAVE ALSO COME DOWN TO 3.5.  THE ADVISORY INTENSITY IS
 SET TO 60 KT.  WHILE THIS MAKES OPHELIA A TROPICAL STORM RATHER
 THAN A HURRICANE... THE WEAKENING IS ONLY SLIGHT AND
 RESTRENGTHENING IS FORECAST.
  
 THE INITIAL MOTION ESTIMATE IS 035/9... BUT THIS NORTHEASTWARD
 MOTION IS DECEPTIVE SINCE IT IS EXPECTED TO PERSIST FOR ONLY ABOUT
 12 MORE HOURS... OR LESS.  AS THE DEEP LAYER TROUGH CURRENTLY OVER
 THE EAST COAST OF THE U.S. PROCEEDS WELL OFFSHORE OVER THE NORTHERN
 ATLANTIC DURING THE NEXT FEW DAYS... A STRONG AND DEEP RIDGE IS
 FORECAST BY ALL OF THE DYNAMICAL MODELS TO BUILD IN ITS PLACE.
 THIS PATTERN SHOULD STOP OPHELIA FROM MOVING OUT TO SEA AND INSTEAD
 PERHAPS FORCE IT WESTWARD AND TOWARD THE SOUTHEAST U.S. COAST.  HOW
 LONG IT WILL TAKE FOR THIS SCENARIO TO EVOLVE IS NOT AGREED UPON BY
 THE DYNAMICAL MODELS. THE GFS SEEMS TO HAVE THE BEST HANDLE ON THE
 CURRENT MOTION...AND IT ALONG WITH THE GFDL BRING OPHELIA TO THE
 COAST THE FASTEST.  CONVERSELY...THE NOGAPS AND UKMET STALL THE
 SYSTEM OFFSHORE LONGER BUT EVENTUALLY BRING IT TO THE COAST.
 ALTHOUGH THIS REMAINS A FAIRLY UNCERTAIN FORECAST...THE NEW
 OFFICIAL FORECAST FAVORS THE GFS AND GFDL SOLUTIONS...AND IS
 SIMILAR TO THE PREVIOUS ADVISORY WITH JUST A SLIGHT ADJUSTMENT
 NORTHWARD.
  
 OPHELIA IS STRUGGLING AGAINST WEST-SOUTHWESTERLY SHEAR AND SOME VERY
 DRY MIDDLE AND UPPER LEVEL AIR OVER THE SOUTHEASTERN STATES...
 ALTHOUGH THIS APPEARS TO BE IMPACTING THE CYCLONE MOSTLY BENEATH
 ITS UPPER LEVEL OUTFLOW LAYER SINCE CIRRUS IS STILL FANNING OUT TO
 THE SOUTHWEST FROM THE CENTER.  THE RIDGE THAT BUILDS NORTH OF
 OPHELIA IN A COUPLE OF DAYS WILL PROBABLY CREATE AN ENVIRONMENT
 MORE CONDUCIVE FOR STRENGTHENING.  THE SHIPS MODEL NOW ONLY PEAKS AT
 68 KT...WHILE GFDL FORECASTS NEAR 85 KT...WITHIN THE NEXT 36 HOURS.
 THE OFFICIAL FORECAST WILL CONTINUE TO SHOW 85 KT PRIOR TO LANDFALL
 GIVEN THE LESS HOSTILE ENVIRONMENT EXPECTED TO UNFOLD SOUTH OF THE
 RIDGE.
  
 WATCHES COULD BE REQUIRED FOR PORTIONS OF THE SOUTHEASTERN U.S.
 COAST LATER TODAY.
  
  
 FORECASTER KNABB
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      10/0900Z 31.2N  76.8W    60 KT
  12HR VT     10/1800Z 31.7N  76.5W    65 KT
  24HR VT     11/0600Z 31.9N  76.7W    70 KT
  36HR VT     11/1800Z 32.0N  77.3W    75 KT
  48HR VT     12/0600Z 32.3N  78.0W    80 KT
  72HR VT     13/0600Z 33.0N  79.5W    85 KT
  96HR VT     14/0600Z 34.5N  79.5W    45 KT...INLAND
 120HR VT     15/0600Z 37.0N  77.5W    30 KT...INLAND
  
  
 $$