WTPN21 PGTW 110230 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 90W) REISSUED// REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/100221ZAPR23// AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT// RMKS/ 1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 160 NM EITHER SIDE OF A LINE FROM 10.3N 134.8E TO 13.7N 126.7E 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 110130Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 13.7N 127.4E. THE SYSTEM IS MOVING WESTWARD AT 17 KNOTS. 2. REMARKS: THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED NEAR 13.0N 130.9E IS NOW LOCATED NEAR 13.7N 127.4E, APPROXIMATELY 217 NM EAST OF LEGAZPI, PHILIPPINES. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS AN AREA OF CONVECTION WITH SIGNS OF WRAPPING IN THE MID-TO-UPPER LEVELS OVER THE NORTHWESTERN EDGE OF AN ASSESSED ELONGATED SURFACE TROUGH. UPON CLOSELY MONITORING THIS DISTURBANCE, THERE IS NOT ENOUGH EVIDENCE SUPPORTING AN UPGRADE TO A TROPICAL CYCLONE AT THIS TIME. A 101223Z ASCAT-B PASS SHOWS WINDS OF 20-25 KTS, WITH A SMALL POCKET OF 30-35 KTS IN A CONCENTRATED AREA TO THE WEST OF THE ASSESSED LOW LEVEL CIRCULATION (LLC). HOWEVER, THESE ELEVATED WINDS APPEAR TO BE ASSOCIATED WITH THUNDERSTORM ACTIVITY AND ARE NOT WRAPPING AROUND THE LLC. A 102152Z SSMIS IMAGE ALONG WITH THE MSI LOOP INDICATE THERE IS MID-TO-UPPER LEVEL WRAPPING OF CONVECTIVE BANDING TAKING PLACE, HOWEVER, THERE IS NO SUGGESTION OF A TIGHTENED SURFACE CIRCULATION DUE TO LACK OF ANY SOUTHERLY FLOW. COMPARISON BETWEEN THE 37 GHZ AND 91 GHZ OF THE SSMIS IMAGES REVEALS THE SYSTEM IS TILTED WITH THE UPPER LEVEL CIRCULATION FURTHER TO THE WEST OF THE LOWER LEVEL CIRCULATION. INVEST 90W IS IN A MARGINALLY FAVORABLE ENVIRONMENT FOR TROPICAL DEVELOPMENT. THESE CONDITIONS ARE CHARACTERIZED BY GOOD POLEWARD AND EQUATORWARD OUTFLOW ALOFT, MODERATE (15-20 KTS) VERTICAL WIND SHEAR (VWS), AND WARM (28-29 C) SEA SURFACE TEMPERATURES (SST). GLOBAL AND DETERMINISTIC MODELS AGREE THAT INVEST 90W WILL TRACK WEST- NORTHWESTWARD AND EVENTUALLY DISSIPATE DUE TO AN INCREASE IN VWS, LAND INTERACTION AND COPIOUS AMOUNTS OF DRY AIR ENTRAINMENT BEING INTRODUCED FROM THE NORTHEAST OVER THE COURSE OF THE NEXT 24-48 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 REMAINS HIGH. THIS SUPERSEDES REF A (WTPN21 PGTW 100230). 3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 120230Z.// NNNN