WTXS21 PGTW 170800 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE FORMATION ALERT(INVEST 96S)// RMKS/ 1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 160 NM EITHER SIDE OF A LINE FROM 12.6S 62.4E TO 14.0S 51.0E 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 27 TO 32 KNOTS. METSAT IMAGERY AT 170600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 12.7S 62.1E. THE SYSTEM IS MOVING WESTWARD AT 24 KNOTS. 2. REMARKS: THE AREA OF CONVECTION (INVEST 96S) PREVIOUSLY LOCATED NEAR 12.4S 64.5E IS NOW LOCATED NEAR 12.7S 62.1E APPROXIMATELY 531 NM NORTH- NORTHEAST OF MAURITIUS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND AN 170335 89GHZ AMSU-B IMAGE DEPICT CURVED DEEP CONVECTIVE BANDING WRAPPING INTO AN AMBIGUOUS, BUT CONSOLIDATING, LOW LEVEL CIRCULATION CENTER (LLCC). UPPER LEVEL ANALYSIS REVEALS A FAVORABLE ENVIRONMENT WITH WARM SEA SURFACE TEMPERATURES (28-29C), LOW VWS (10-15KT) AND GOOD EQUATORWARD AND POLEWARD OUTFLOW. GLOBAL MODELS ARE IN GOOD AGREEMENT WITH 96S TRACKING WESTWARD WITH STEADY DEVELOPMENT AND INTENSIFICATION IN THE NEXT 12-36 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 27 TO 32 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 999 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 180800Z. // NNNN