Hurricane OPHELIA

ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM OPHELIA DISCUSSION NUMBER  25
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 AM EDT MON SEP 12 2005

LATEST DATA FROM THE AIR FORCE RECONNAISSANCE INDICATED A PEAK 700
MB FLIGHT LEVEL WIND OF 63 KT.  MAXIMUM SURFACE WINDS ARE ESTIMATED
TO BE NEAR 60 KT...ALTHOUGH THIS IS PROBABLY GENEROUS GIVEN THE
LACK OF DEEP CONVECTION TO TRANSPORT MOMENTUM VERTICALLY.  THUS THE
SYSTEM IS BEING DOWNGRADED TO A TROPICAL STORM ON THIS ADVISORY.
OPHELIA HAS NOT MOVED MUCH OVER THE LAST COUPLE OF DAYS...SO
UPWELLING AND STIRRING HAS LIKELY COOLED THE WATERS.  SHIP AND
DRIFTING BUOY DATA SUGGEST THAT THE SEA SURFACE TEMPERATURES MAY
HAVE DECREASED TO BELOW 26 DEG C BENEATH THE STORM CENTER.  THE
TRACK FORECAST TAKES OPHELIA OVER A SECTION OF THE GULF STREAM...
WHERE A MODESTLY DEEP WARM WATER MIXED LAYER...I.E. HIGHER OCEANIC
HEAT CONTENT...COULD INDUCE RE-STRENGTHENING.  THEREFORE THE
OFFICIAL FORECAST SHOWS THE SYSTEM RE-ATTAINING HURRICANE STRENGTH
BEFORE NEARING THE COAST.

AFTER COMPLETING A SMALL CLOCKWISE LOOP...THE STORM IS MOVING VERY
SLOWLY NORTHWESTWARD...315/02.  BECAUSE THE STEERING CURRENTS ARE
SO ILL-DEFINED...THE TRACK FORECAST REMAINS A DIFFICULT ONE.  SOME
GLOBAL MODELS...NAMELY NOGAPS AND THE CANADIAN...INDICATE THAT THE
BROAD 500 MB TROUGH APPROACHING THE EASTERN UNITED STATES IN A
COUPLE OF DAYS WILL LACK SUFFICIENT AMPLITUDE TO PICK UP OPHELIA
AND ACCELERATE IT NORTHEASTWARD.  THEREFORE WE HAVE THE UNPLEASANT 
POSSIBILITY THAT THE CYCLONE COULD LINGER NEAR THE SOUTHEAST U.S.
THROUGH 5 DAYS.  THE GFS AND GFDL STILL MOVE OPHELIA NORTHEASTWARD
OVER THE ATLANTIC BEYOND 3 DAYS...BUT THEY ARE SOMEWHAT SLOWER THAN
THEIR PREVIOUS RUNS.  IN DEFERENCE TO THIS NUMERICAL GUIDANCE...THE
OFFICIAL FORECAST IS A BIT SLOWER THAN THE PREVIOUS ONE IN THE 3-5
DAY TIME FRAME.

FORECASTER PASCH
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      12/1500Z 31.6N  76.8W    60 KT
 12HR VT     13/0000Z 31.8N  77.4W    60 KT
 24HR VT     13/1200Z 32.3N  77.7W    65 KT
 36HR VT     14/0000Z 33.0N  77.7W    65 KT
 48HR VT     14/1200Z 33.9N  77.4W    70 KT
 72HR VT     15/1200Z 35.5N  76.0W    65 KT
 96HR VT     16/1200Z 38.0N  73.0W    55 KT
120HR VT     17/1200Z 41.0N  68.0W    45 KT...EXTRATROPICAL
 
 
$$
NNNN