WTXS21 PGTW 200830 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 95S)// RMKS/ 1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 105NM EITHER SIDE OF A LINE FROM 10.9S 52.8E TO 9.6S 47.0E 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 28 TO 33 KNOTS. METSAT IMAGERY AT 200600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 10.8S 52.4E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 14 KNOTS. 2. REMARKS: THE AREA OF CONVECTION (INVEST 95S) PREVIOUSLY LOCATED NEAR 11.1S 53.8E IS NOW LOCATED NEAR 10.8S 52.4E, APPROXIMATELY 634 NM NORTH-NORTHWEST OF MAURITIUS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND A 200256Z SSMIS 91GHZ MICROWAVE IMAGE REVEAL FORMATIVE BANDING WITH CYCLING CONVECTION TO THE NORTHEAST AND SOUTH OF THE LOW LEVEL CIRCULATION CENTER (LLCC). A 200623Z ASCAT-B BULLSEYE PASS SHOWS A WELL DEFINED LLCC AND AN ASYMMETRIC WIND FIELD, WITH 25-30KT WINDS AND A RELATIVELY SMALLER AREA OF 30-35KT WINDS IN THE SOUTHERN SEMICIRCLE. THE AFOREMENTIONED DATA LEND HIGH CONFIDENCE TO THE ANALYSIS POSITION. INVEST 95S IS IN AN ENVIRONMENT CONDUCIVE FOR INTENSIFICATION, WITH MODERATE EQUATORWARD AND EASTWARD OUTFLOW ALOFT, LOW TO MODERATE (15-20KTS) VERTICAL WIND SHEAR, AND WARM (29- 30C) SEA SURFACE TEMPERATURES. GLOBAL MODELS ARE IN GENERAL AGREEMENT THAT INVEST 95S WILL TRACK WESTWARD AS IT INTENSIFIES AND PASSES NORTH OF MADAGASCAR OVER THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 28 TO 33 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 998 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 210830Z.// NNNN