HOME	ACTIVE CYCLONES	FORECASTS	IMAGERY	ABOUT TPC	RECONNAISSANCE

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HURRICANE GERT DISCUSSION NUMBER  13
NATIONAL WEATHER SERVICE MIAMI FL
10 AM EST TUE SEP 14 1999
 
SATELLITE IMAGERY SHOWS GERT HAS A WELL DEVELOPED EYE. SATELLITE
INTENSITY ESTIMATES FROM TAFB AND SAB ARE 90 KT...WHICH WILL BE THE
MAXIMUM INTENSITY FOR THIS ADVISORY.
 
THE INITIAL MOTION IS LESS ESTIMATED TO BE 285/14. THE SYNOPTIC
PATTERN IS BASICALLY UNCHANGED. WITH GERT CONTINUING WEST TO WEST-
NORTHWEST UNDER THE SUBTROPICAL RIDGE. THE RIDGE SEEMS TO STRENGTHEN
BEHIND FLOYD...KEEPING GERT ON A WEST TO WEST-NORTHWEST TRACK.
SEVERAL HURRICANE GUIDANCE MODELS...MOST NOTABLY THE NOGAPS AND THE
BAMM...HAVE A TURN TOWARD THE NORTHWEST DUE TO A WEAKENING RIDGE
NEAR THE END OF THE FORECAST PERIOD. THIS APPEARS TO BE THE
INFLUENCE OF FLOYD, AND MAY NOT BE REALIZED IF FLOYD MOVES ON OUT
AND IS INDEED NORTH OF OR NEAR THE RIDGELINE. THE OFFICIAL FORECAST
IS SHIFTED ONLY SLIGHTLY NORTHWARD FROM THE PREVIOUS PACKAGE. WHILE
THE FORECAST KEEPS GERT NORTH OF THE LEEWARDS...GERT COULD STILL BE
A THREAT TO THAT AREA IF THE STORM MOVES MORE TO THE WEST THAN
CURRENTLY FORECAST.
 
THERE IS NO CHANGE IN THE INTENSITY FORECAST FROM THE PREVIOUS
CYCLE.  BASICALLY THIS AGREES WITH SHIFOR AND IS SLIGHTLY STRONGER
THAN SHIPS.  SHIPS INDICATES AN INCREASE IN WIND SHEAR THAT ALSO MAY
BE RELATED TO FLOYD.

JARRELL
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     14/1500Z 17.1N  45.3W    90 KTS
12HR VT     15/0000Z 17.5N  47.4W    95 KTS
24HR VT     15/1200Z 18.1N  50.4W   100 KTS
36HR VT     16/0000Z 18.7N  53.0W   105 KTS
48HR VT     16/1200Z 19.1N  55.7W   110 KTS
72HR VT     17/1200Z 20.0N  61.0W   110 KTS
 
 
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