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TROPICAL STORM ISIDORE DISCUSSION NUMBER  38
NATIONAL WEATHER SERVICE MIAMI FL
11 AM EDT WED SEP 25 2002
 
ISIDORE CONTINUES AS A LARGE STEADY-STATE CYCLONE THIS MORNING.
BUOY OBSERVATIONS AND REPORTS FROM A NOAA RECONNAISSANCE AIRCRAFT
INDICATE THE CENTRAL PRESSURE REMAINS NEAR 990 MB.  THE AIRCRAFT
INDICATED THAT THE MAXIMUM WINDS WERE STILL WELL-REMOVED FROM THE
CENTER...WITH A MAXIMUM 850 MB WIND OF 67 KT.  TWO SHIPS TO THE
NORTHEAST OF THE CENTER REPORTED 50-55 KT WINDS WITH GUSTS AS HIGH 
AS 65 KT.  BASED ON THIS...THE MAXIMUM SUSTAINED WINDS REMAIN 50 KT.
IT SHOULD BE NOTED THAT WATER VAPOR IMAGERY INDICATES THAT AN
UPPER-LEVEL LOW MAY BE FORMING TO THE SOUTHWEST OF THE LOW-LEVEL
CENTER WITH DRIER AIR POURING INTO THE SOUTHERN PART OF THE 
STORM.  THIS SUGGESTS ISIDORE MAY BE LOSING SOME OF ITS TROPICAL
CHARACTER. 
 
THE INITIAL MOTION IS 355/11.  THERE IS LITTLE CHANGE IN THE 
SYNOPTIC PATTERN OR FORECAST TRACK REASONING.  ISIDORE IS MOVING
NORTHWARD BETWEEN RIDGING OVER THE FLORIDA PENINSULA AND BROAD
TROUGHING OVER THE CENTRAL UNITED STATES.  THE STORM SHOULD TURN
NORTHEASTWARD AND ACCELERATE AFTER 24 HR AS IT ENTERS THE 
WESTERLIES.  NHC TRACK GUIDANCE IS IN GOOD AGREEMENT WITH THIS
SCENARIO AND SO IS THE OFFICIAL FORECAST...WHICH IS BASICALLY AN
UPDATE OF THE PREVIOUS PACKAGE.
 
THE FORMATION OF THE UPPER-LEVEL LOW AND THE DRY AIR ENTRAINMENT
SUGGESTS THAT THE CHANCES OF ISIDORE BECOMING A HURRICANE HAVE
DECREASED.  HOWEVER...THE CONVECTION IS MORE INTENSE...BETTER 
WRAPPED...AND CLOSER TO THE CENTER THAN 24 HOURS AGO.  THIS
SUGGESTS THAT SOME DEVELOPMENT IS OCCURRING IN SPITE OF THE UPPER
LOW.  THE INTENSITY FORECAST WILL CALL FOR SLIGHT STRENGTHENING...
AND THERE IS STILL A CHANCE THAT ISIDORE COULD REACH HURRICANE 
STRENGTH BEFORE LANDFALLL.  AFTER LANDFALL...THE CYCLONE SHOULD
WEAKEN AND BECOME EXTRATROPICAL BY 48 HR..FOLLOWED BY SOME
RE-DEVELOPMENT AS AN EXTRATROPICAL LOW.

THE TROPICAL STORM WARNING WAS EXTENDED EASTWARD BASED ON EXPANSION
OF THE WIND FIELD SHOWN BY BUOY 42003.
 
FORECASTER BEVEN
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     25/1500Z 26.0N  90.2W    50 KTS
12HR VT     26/0000Z 27.9N  90.3W    55 KTS
24HR VT     26/1200Z 30.0N  90.2W    50 KTS...INLAND
36HR VT     27/0000Z 33.0N  89.3W    30 KTS...INLAND
48HR VT     27/1200Z 37.3N  85.3W    25 KTS...INLAND EXTRATROPICAL
72HR VT     28/1200Z 46.5N  65.5W    35 KTS...INLAND EXTRATROPICAL
 
 
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