WTPN21 PGTW 290230
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 15.8N 136.5E TO 16.5N 131.1E
WITHIN THE NEXT 06 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 290000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 15.8N 136.2E. THE SYSTEM IS MOVING WESTWARD AT 10 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 93) PREVIOUSLY LOCATED NEAR 
15.4N 141.5E IS NOW LOCATED NEAR 15.8N 136.2E, APPROXIMATELY 877 NM EAST 
OF MANILA, PHILIPPINES. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND A 
282147Z SSMIS 91GHZ SATELLITE IMAGE SHOW MID-LEVEL TURNING AND SHALLOW 
RAIN BANDS WRAPPING INTO A WELL-DEFINED, PARTLY EXPOSED LOW-LEVEL 
CIRCULATION CENTER. ENVIRONMENTAL ANALYSIS REVEALS THE INVEST IS IN A 
FAVORABLE ENVIRONMENT FOR DEVELOPMENT DEFINED BY ROBUST EQUATORWARD 
OUTFLOW, FAVORABLE (10-15 KT) VERTICAL WIND SHEAR, AND VERY WARM (30-31C) 
SEA SURFACE TEMPERATURES. THE INVEST IS ALSO IN AN AREA WITH A RELATIVELY 
PRONOUNCED 850 MB VORTICITY SIGNATURE. GLOBAL MODELS ARE IN GENERAL 
AGREEMENT THAT 93W WILL TRACK WEST TO WEST-NORTHWESTWARD AND INTENSIFY AS 
IT APPROACHES NORTHERN LUZON. 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 
300230Z.
//
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