WTPN21 PGTW 101730 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 93W)// RMKS/ 1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 120 NM EITHER SIDE OF A LINE FROM 20.8N 159.6E TO 22.8N 162.7E 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 18 TO 23 KNOTS. METSAT IMAGERY AT 101700Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 20.9N 159.8E. THE SYSTEM IS MOVING EAST-NORTHEASTWARD AT 06 KNOTS. 2. REMARKS: THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED NEAR 21.5N 158.4E IS NOW LOCATED NEAR 20.9N 159.8E, APPROXIMATELY 396 NM WEST-NORTHWEST OF WAKE ISLAND. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A LOW LEVEL CIRCULATION (LLC) WITH DEEP CONVECTION IN THE SOUTHERN PERIPHERY OF THE SYSTEM. THERE IS WEAK BANDING WRAPPING INTO THE LLC. A PARTIAL 101029Z ASCAT METOP-B 25KM PASS SHOWS 15-20KT WINDS FROM THE SOUTHWEST. ENVIRONMENTAL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT FOR TROPICAL DEVELOPMENT WITH STRONG EQUATORWARD OUTFLOW, WARM (29-30C) SEA SURFACE TEMPERATURES, AND LOW TO MODERATE (15-20 KNOTS) VERTICAL WIND SHEAR. GLOBAL MODELS ARE IN AGREEMENT THAT INVEST 93W WILL TRACK NORTH- NORTHEAST AND CONTINUE TO CONSOLIDATE OVER THE NEXT 24-36 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005 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 111730Z. // NNNN