WTIO21 PGTW 300930
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
080 NM EITHER SIDE OF A LINE FROM 6.5N 87.5E TO 6.3N 85.1E 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 25 TO 30 KNOTS. METSAT IMAGERY AT
300830Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 6.5N
87.3E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 10 KNOTS.
2. REMARKS:
ANIMATED ENHANCED MULTISPECTRAL IMAGERY (EMI) DISPLAYS AN AREA OF 
FLARING CONVECTION THAT IS OBSCURING A BROAD LOW LEVEL CIRCULATION. 
A PARTIAL 300711Z AMSR2 89GHZ PASS SHOWS FORMATIVE BANDING WITH DEEP 
CONVECTION IN THE NORTHEAST PERIPHERY. ENVIRONMENTAL ANALYSIS 
INDICATES FAVORABLE CONDITIONS FOR TROPICAL DEVELOPMENT WITH ROBUST
POLEWARD AND WESTWARD OUTFLOW ALOFT, LOW (5-10 KTS) VERTICAL WIND 
SHEAR (VWS), AND WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES. 
NUMERICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT THAT INVEST 98B WILL 
CONTINUE TO CONSOLIDATE AND INTENSIFY AS IT TRACKS WEST-
NORTHWESTWARD TOWARD SRI LANKA. MAXIMUM SUSTAINED SURFACE WINDS ARE 
ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED 
TO BE NEAR 1000 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 
010930Z.
//
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