WTPN21 PGTW 110930 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 135 NM EITHER SIDE OF A LINE FROM 17.0N 119.4E TO 18.0N 114.9E 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 15 TO 20 KNOTS. METSAT IMAGERY AT 110600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 17.0N 118.9E. THE SYSTEM IS MOVING WESTWARD AT 08 KNOTS. 2. REMARKS: THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED NEAR 16.9N 119.2E IS NOW LOCATED NEAR 17.0N 118.9E, APPROXIMATELY 183 NM NORTHWEST OF MANILA, PHILIPPINES. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND AN 110547Z AMSR2 89GHZ MICROWAVE IMAGE REVEAL SHALLOW FRAGMENTED FORMATIVE BANDING WRAPPING INTO A LOW LEVEL CIRCULATION WITH LIMITED DEEP CONVECTION. AN 110204Z ASCAT-B PASS REVEALS MAINLY 10-15KT WINDS WITH SOME 20KT WINDS DISPLACED TO THE NORTH. INVEST 93W IS IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH LOW (<15KTS) VERTICAL WIND SHEAR, MODERATE UPPER LEVEL DIFFLUENCE, AND WARM (29-30C) SEA SURFACE TEMPERATURES. GLOBAL MODELS ARE IN STRONG AGREEMENT THAT INVEST 93W WILL QUICKLY CONSOLIDATE AND TRACK WEST-NORTHWESTWARD ACROSS THE SOUTH CHINA SEA. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 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 120930Z.// NNNN