WTPS21 PGTW 081500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
180 NM EITHER SIDE OF A LINE FROM 16.0S 179.5E TO 22.6S 179.2W
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 27 TO 32 KNOTS. METSAT
IMAGERY AND SYNOPTIC DATA AT 081430Z INDICATE THAT A CIRCULATION
CENTER IS LOCATED NEAR 16.9S 179.8E. THE SYSTEM IS MOVING SOUTH-
SOUTHEASTWARD AT 10 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 92P) PREVIOUSLY LOCATED 
NEAR 15.1S 179.1E IS NOW LOCATED NEAR 16.9S 179.8E, APPROXIMATELY 
145 NM EAST-NORTHEAST OF NADI, FIJI. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY DEPICTS FLARING, DEEP CONVECTION SURROUNDING
A BROAD AREA OF LOW LEVEL CIRCULATION. A 080958Z ASCAT-B PASS REVEALS
THAT THE LOW LEVEL CIRCULATION IS ELONGATED ALONG THE NORTH-SOUTH
AXIS AND CONTAINS 30-35 KTS WINDS IN THE CONVERGENT FLOW ALONG THE
EASTERN PERIPHERY, ALTHOUGH THE WINDS NEAR THE CENTER OF THE ELONGATED
CIRCULATION REMAIN RELATIVELY WEAK (10-15 KTS). ENVIRONMENTAL ANALYSIS 
DEPICTS A MARGINALLY FAVORABLE ENVIRONMENT WITH MODERATE UPPER LEVEL 
OUTFLOW ALOFT AND WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES OFFSET 
SLIGHTLY BY MODERATE (15-20 KTS) VERTICAL WIND SHEAR ALONG THE SOUTHERN
PERIPHERY OF THE SYSTEM. NUMERICAL MODEL SOLUTIONS ARE CONVERGING
ON A SOUTHWESTWARD TRACK WITH SUBSEQUENT CONSOLIDATION INTO A TROPICAL 
CYCLONE WITHIN THE NEXT 24-48 HOURS. MAXIMUM SUSTAINED SURFACE WINDS 
ARE ESTIMATED AT 27 TO 32 KNOTS. MINIMUM SEA LEVEL PRESSURE IS 
ESTIMATED TO BE NEAR 999 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 
091500Z.//
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