WTPS21 PGTW 210300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 90P)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 7.2S 168.7E TO 11.1S 166.8E
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 25 TO 30 KNOTS. METSAT
IMAGERY AT 210230Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 7.4S 168.6E. THE SYSTEM IS MOVING SOUTH-SOUTHWESTWARD AT 06
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 90P) PREVIOUSLY LOCATED NEAR 
7.1S 169.3E IS NOW LOCATED NEAR 7.4S 168.8E, APPROXIMATELY 525 NM EAST-
NORTHEAST OF HONIARA, SOLOMON ISLANDS. ANIMATED MULTISPECTRAL SATELLITE 
IMAGERY DEPICTS A CONSOLIDATING, PARTIALLY EXPOSED LOW-LEVEL CIRCULATION 
CENTER (LLCC) WITH PERSISTENT DEEP CONVECTION AND FORMATIVE BANDING IN 
THE NORTHERN AND EASTERN PERIPHERIES. A 202237Z ASCAT-C IMAGE REVEALS 
SPARSE 30 KT WINDS SOUTH OF THE CIRCULATION CENTER. ENVIRONMENTAL 
ANALYSIS INDICATES THAT 90P IS IN A FAVORABLE ENVIRONMENT FOR 
DEVELOPMENT WITH GOOD OUTFLOW ALOFT, LOW (10-15 KTS) VERTICAL WIND 
SHEAR, AND WARM (29-30 C) SST. GLOBAL MODELS ARE IN GOOD AGREEMENT THAT 
90P WILL TRACK SOUTH-SOUTHWESTWARD AND CONTINUE TO DEVELOP OVER THE NEXT 
24-48 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 
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 
220300Z.
//
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