WTPN21 PGTW 292130
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 11.3N 113.4E TO 13.0N 109.4E
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 18 TO 23 KNOTS. METSAT
IMAGERY AT 291800Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 11.4N 113.2E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 12
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED  
NEAR 10.8N 114.3E IS NOW LOCATED NEAR 10.8N 113.2E, APPROXIMATELY  
407NM SOUTHEAST OF DANANG, VIETNAM. 93W HAS CONSOLIDATED OVER THE 
LAST 12 HOURS WITH THE STRONG MID-LEVEL TURNING GRADUALLY BURROWING 
DOWN TO THE SURFACE, THOUGH THE WEAK LOW LEVEL CIRCULATION (LLC) 
REMAINS OBSCURED BY MID AND UPPER-LEVEL CLOUDS. ENVIRONMENTAL 
ANALYSIS INDICATES PRIME CONDITIONS FOR DEVELOPMENT WITH NEAR-RADIAL 
OUTFLOW WITH LOW (05-10KT) VERTICAL WIND SHEAR AND WARM (29-30C) SEA 
SURFACE TEMPERATURES. THE MAIN HINDRANCES AT THE MOMENT ARE THE 
RELATIVELY SHORT TIME REMAINING OVER WATER AND THE RELATIVELY SLOW 
CONSOLIDATION OF THE LLC. GFS REMAINS THE MOST AGGRESSIVE MODEL WITH 
A TROPICAL DEPRESSION DEVELOPING QUICKLY WITHIN THE NEXT 18-36 HOURS 
AS THE SYSTEM TRACKS NORTHWESTWARD TOWARD VIETNAM. ECMWF AND NAVGEM 
SHOW A SIMILAR TRACK BUT WITH SIGNIFICANTLY LESS DEVELOPMENT. THE 
GFS SOLUTION APPEARS MORE LIKELY CONSIDERING THE FAVORABLE 
ENVIRONMENTAL CONDITIONS. MAXIMUM SUSTAINED SURFACE WINDS ARE 
ESTIMATED AT 12 TO 18 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED 
TO BE NEAR 1006 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A 
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO 
HIGH. 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 
302130Z.
//
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