WTXS21 PGTW 232300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 92S)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 19.5S 57.5E TO 24.3S 60.0E
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 232300Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 20.1S 57.9E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 09
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 92S) PREVIOUSLY LOCATED 
NEAR 19.6S 58.8E IS NOW LOCATED NEAR 20.1S 57.9E, APPROXIMATELY 23 NM 
EAST-NORTHEAST OF MAURITIUS. ANIMATED ENHANCED INFRARED SATELLITE 
IMAGERY (EIR) AND A PARTIAL 2317157Z METOP-B ASCAT DEPICT A 
CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC) WITH THE STRONGEST 
WIND ASSOCIATED WITH PERSISTENT FLARING CONVECTION PLACED TO THE WEST-
NORTHWEST. A RECENT MAURITIUS OBSERVATION SHOWS A DYNAMIC DROP IN 
PRESSURE BY 7 MB IN THE LAST 24 HOURS, WHILE A SHIP OBSERVATION TO 
SOUTHWEST SHOWS SOUTHERLY WINDS AT 28 KNOTS. ENVIRONMENTAL ANALYSIS 
INDICATES THAT 92S IS IN A MARGINALLY FAVORABLE ENVIRONMENT FOR 
FURTHER DEVELOPMENT WITH WEAK EQUATORWARD OUTFLOW ALOFT, LOW TO 
MODERATE (15-20 KTS) VERTICAL WIND SHEAR, AND WARM (28-29 C) SEA 
SURFACE TEMPERATURES. MODEL GUIDANCE INDICATES THAT THE SYSTEM IS 
CURRENTLY PASSING MAURITIUS AND WILL CONTINUE TO BECOME MORE ORGANIZED 
OVER THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED 
AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 
998 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 
242300Z.//
NNNN