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TROPICAL STORM HELENE DISCUSSION NUMBER  16
NATIONAL WEATHER SERVICE MIAMI FL
5 AM EDT FRI SEP 22 2000
 
IF I DID NOT HAVE A RECONNAISSANCE PLANE IN THE AREA...I WOULD NOT
KNOW THERE IS A TROPICAL CYCLONE BY JUST OBSERVING IR SATELLITE
IMAGERY.  STRONG WESTERLY SHEAR...LIKE IN MOST OF THE TROPICAL
CYCLONES THIS YEAR...REMOVED THE DEEP CONVECTION AND HELENE IS NOW A
TIGHT SWIRL OF LOW CLOUDS WITH A FEW PATCHES OF DEEP CONVECTION. 
THE CENTRAL PRESSURE HAS RISEN TO 1003 MB AND MAXIMUM FLIGHT LEVEL
WINDS ARE 50 KNOTS IN A FEW AREAS TO THE EAST OF THE CENTER. 
INITIAL INTENSITY HAS BEEN ADJUSTED TO 45 KNOTS. 

HELENE HAS BEEN STEERED NORTHWARD AROUND THE PERIPHERY OF A
SUBTROPICAL RIDGE BUT NOW THAT IT IS A SHALLOW SYSTEM IT COULD
CONTINUE NORTHWARD OR EVEN NORTH-NORTHWESTWARD FOR 12 MORE HOURS
STEERED BY THE LOW-LEVEL FLOW.  THEREAFTER...HELENE SHOULD GRADUALLY
BEGIN TO INTERACT WITH A FRONTAL ZONE AND TURN TOWARD THE NORTHEAST
BECOMING EXTRATROPICAL.  THE AREA OF MINIMUM PRESSURE SHOULD BE
CROSSING THE COAST IN ABOUT 3 TO 6 HOURS BUT MOST OF THE WEATHER IS
TO THE NORTH AND EAST...REMOVED FROM THE CENTER.  IN FACT... MOST OF
THE WEATHER IS ALREADY CROSSING THE COAST.
 
FORECASTER AVILA
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     22/0900Z 30.0N  87.4W    45 KTS
12HR VT     22/1800Z 31.5N  87.0W    35 KTS...INLAND
24HR VT     23/0600Z 34.0N  83.5W    25 KTS...INLAND
36HR VT     23/1800Z 36.0N  80.0W    20 KTS...INLAND
48HR VT     24/0600Z 37.5N  75.0W    30 KTS...EXTRATROPICAL
72HR VT     25/0600Z 42.0N  65.0W    30 KTS...EXTRATROPICAL
 
 
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