WTXS21 PGTW 160030
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 90S)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
145 NM EITHER SIDE OF A LINE FROM 8.3S 91.7E TO 9.1S 87.1E 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 28 TO 33 KNOTS. METSAT IMAGERY AT
170000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 8.2S
91.4E. THE SYSTEM IS MOVING SOUTHWARD AT 06 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 90S) PREVIOUSLY LOCATED NEAR 
7.2S 91.3E IS NOW LOCATED NEAR 8.2S 91.4E, APPROXIMATELY 401 NM 
NORTHWEST OF THE COCOS ISLANDS. ANIMATED ENHANCED INFRARED SATELLITE 
IMAGERY (EIR) DEPICT AN AREA OF CURVED CONVECTIVE BANDING SURROUNDING 
THE SOUTHERN PERIPHERY OF A WELL-DEFINED LOW LEVEL CIRCULATION CENTER 
(LLCC). ENVIRONMENTAL CONDITIONS ARE MODERATELY FAVORABLE WITH GOOD 
POLEWARD OUTFLOW ALOFT AND WARM (29-30 C) SEA SURFACE TEMPERATURES. THE 
ONLY HINDRANCE BEING MODERATE TO HIGH (20-25 KNOTS) VERTICAL WIND SHEAR 
IMPACTING 90S FROM THE EAST. CURRENT GLOBAL DETERMINISTIC AND ENSEMBLE 
MODELS ARE IN GOOD AGREEMENT ON A SLOW SOUTHWESTWARD TRACK WITH MARGINAL 
FURTHER DEVELOPMENT OVER THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE 
WINDS ARE ESTIMATED AT 28 TO 33 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 
170030Z.
//
NNNN