Hurricane OPHELIA

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HURRICANE OPHELIA DISCUSSION NUMBER  24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM EDT MON SEP 12 2005
 
THE LAST RECON FIX AT 06Z MEASURED A CENTRAL PRESSURE OF 985 MB... A
LITTLE HIGHER THAN BEFORE... AND MAXIMUM 700 MB FLIGHT LEVEL WINDS
DURING THE PAST SEVERAL HOURS WERE 78 KT IN THE NORTHWESTERN
QUADRANT.  HOWEVER... IT IS NOT CERTAIN THAT THESE WINDS ARE MIXING
DOWN TO THE SURFACE AS MUCH AS THE AVERAGE REDUCTION WOULD DICTATE.
SINCE THE PRESSURE HAS BEEN RISING AND THE SATELLITE APPEARANCE NOT
ANY MORE IMPRESSIVE... THE ADVISORY INTENSITY IS KEPT AT 65 KT. 
THE INTENSITY FORECAST AND REASONING ARE ESSENTIALLY THE SAME AS
THE PREVIOUS ADVISORY.  THE SHIPS MODEL NO LONGER FORECASTS THE
WEAKENING THAT IT HAD PREVIOUSLY AND IS NOW MORE SUPPORTIVE OF THE
MINIMAL CHANGES IN INTENSITY SHOWN IN THE OFFICIAL FORECAST THROUGH
72 HOURS... UNTIL WEAKENING AND EVENTUAL EXTRATROPICAL TRANSITION
OVER COOLER WATERS FARTHER NORTHEAST.
 
CONSECUTIVE RECON FIXES THROUGH 06Z INDICATED AN ESTIMATED INITIAL
MOTION OF 270/4.  OPHELIA HAS COMPLETED A SMALL CLOCKWISE LOOP AND
IS BACK WHERE IT WAS ABOUT 48 HOURS AGO.  WHILE THE TRACK FORECAST
REASONING HAS NOT SIGNIFICANTLY CHANGED... SOME OF THE MODELS ARE
PROVIDING NEW AND DIVERGENT SOLUTIONS.  NONE OF THE RELIABLE
DYNAMICAL MODELS HAVE BEEN IMMUNE FROM SIGNIFICANT TRACK FORECAST
SHIFTS DURING THE PAST DAY OR TWO IN THIS VERY DIFFICULT SCENARIO. 
THE LATEST RUNS INCLUDE THE GFDL SHIFTING BACK TO THE EAST CLOSER
TO THE PREVIOUS OFFICIAL FORECAST.  HOWEVER...THE UKMET AND
ESPECIALLY THE NOGAPS NOW SUGGEST THAT OPHELIA WILL NOT GET PICKED
UP BY THE NEXT MIDLATITUDE TROUGH EXPECTED TO APPROACH THE EAST
COAST OF THE U.S. IN ABOUT THREE DAYS.  AS A RESULT THESE MODELS
FORECAST OPHELIA TO STILL BE NOT FAR OFF THE COAST OF THE CAROLINAS
4-5 DAYS FROM NOW.  EVEN THOUGH NOGAPS IS A CREDIBLE MODEL... SINCE
THE NOGAPS SOLUTION IS A NEW ONE I AM NOT READY TO MAKE SIGNIFICANT
ADJUSTMENTS TO THE OFFICIAL FORECAST.  ACCOUNTING FOR THE
POSSIBILITY THAT NOGAPS AND UKMET COULD BE AT LEAST PARTIALLY
CORRECT... THE OFFICIAL FORECAST IS SLOWER THAN THE PREVIOUS
ADVISORY BUT IS ALONG THE SAME PATH... ANTICIPATING A SLOW AND
GRADUAL TURN TO THE NORTH AND EVENTUALLY NORTHEAST DURING THE NEXT
FIVE DAYS.
 
 
FORECASTER KNABB
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      12/0900Z 31.3N  76.7W    65 KT
 12HR VT     12/1800Z 31.4N  77.2W    65 KT
 24HR VT     13/0600Z 31.9N  77.5W    65 KT
 36HR VT     13/1800Z 32.5N  77.6W    70 KT
 48HR VT     14/0600Z 33.3N  77.5W    70 KT
 72HR VT     15/0600Z 35.5N  76.0W    70 KT
 96HR VT     16/0600Z 38.5N  72.5W    55 KT
120HR VT     17/0600Z 42.0N  68.0W    45 KT...EXTRATROPICAL
 
 
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