WTPN21 PHNC 051500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 91E)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
130 NM EITHER SIDE OF A LINE FROM 9.0N 90.1W TO 11.6N 95.9W
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 22 TO 28 KNOTS. METSAT
IMAGERY AT 051200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 9.1N 90.4W. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 10
KNOTS.
2. REMARKS: AN AREA OF CONVECTION (INVEST 91E) IS LOCATED NEAR 9.1N 
90.4W, APPROXIMATELY 282NM SOUTH-SOUTHWEST OF SAN SALVADOR, MEXICO. 
ANIMATED MULTISPECTRAL IMAGERY (MSI) DEPICTS AN ELONGATED AREA WITH 
BROAD TURNING AND FLARING CONVECTION, AS IT ATTEMPTS TO BECOME A 
DEFINED LOW LEVEL CIRCULATION CENTER (LLCC). ENVIRONMENTAL ANALYSIS 
REVEALS FAVORABLE CONDITIONS FOR DEVELOPMENT WITH LOW VERTICAL WIND 
SHEAR (LESS THAN 15 KNOTS), WARM SEA SURFACE TEMPERATURE (28-29C), AND 
GOOD OUTFLOW ALOFT. GLOBAL MODELS ARE IN AGREEMENT THAT INVEST 91E 
WILL CONTINUE TO DEVELOP OVER THE NEXT 24 HOURS AND HAVE A 
NORTHWESTWARD TRACK. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 
22 TO 28 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 
061500Z.//
NNNN