WTXS21 PGTW 040300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 90S)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
100 NM EITHER SIDE OF A LINE FROM 16.9S 83.7E TO 20.1S 82.9E
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 25 TO 30 KNOTS. METSAT
IMAGERY AT 040000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 17.2S 83.6E. THE SYSTEM IS MOVING SOUTHWARD AT 07 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 90S) PREVIOUSLY LOCATED 
NEAR 16.5S 83.6E IS NOW LOCATED NEAR 17.2S 83.6E, APPROXIMATELY 871 
NM NORTH OF DIEGO GARCIA. ANIMATED ENHANCED INFRARED SATELLITE 
IMAGERY DEPICTS DEEP FLARING CONVECTION PARTIALLY OBSCURING AN 
ELONGATED LOW LEVEL CIRCULATION (LLC). RECENT SCATTEROMETRY DATA 
REVEALS WINDS OF UP TO 30 KNOTS OFFSET TO THE SOUTH OF THE LLC. 
ENVIRONMENTAL ANALYSIS INDICATES FAVORABLE CONDITIONS FOR 
DEVELOPMENT DEFINED BY; ROBUST OUTFLOW ALOFT, LOW TO MODERATE (15-
20KT) VERTICAL WIND SHEAR, AND WARM (28-29C) SEA SURFACE 
TEMPERATURES. GLOBAL MODELS ARE IN AGREEMENT THAT INVEST 90S WILL 
CONTINUE TO INTENSIFY AS IT TRACKS EQUATORWARD BEFORE TURNING TO A 
MORE WEST-SOUTHWESTWARD TRACK AROUND TAU 36. MAXIMUM SUSTAINED 
SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL 
PRESSURE IS ESTIMATED TO BE NEAR 1000 MB. THE POTENTIAL FOR THE 
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 
HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 
050300Z.
//
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