WTXS21 PGTW 210200
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 93W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
130 NM EITHER SIDE OF A LINE FROM 15.4S 57.7E TO 17.4S 52.1E 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 210100Z 
INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 15.9S 57.0E. THE 
SYSTEM IS MOVING SOUTHWESTWARD AT 13 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 93S) PREVIOUSLY LOCATED 
NEAR 14.5S 58.6E IS NOW LOCATED NEAR 15.9S 57.0E, APPROXIMATELY 565 
NM EAST-NORTHEAST OF ANTANANARIVO, MADAGASCAR. ANIMATED 
MULTISPECTRAL SATELLITE IMAGERY DEPICTS A COMPACT SYSTEM WITH 
FORMATIVE BANDING IN THE WESTERN AND NORTHERN QUADRANTS FEEDING INTO 
A FULLY OBSCURED LOW LEVEL CIRCULATION (LLC). A 201819Z ASCAT METOP-
C PASS INDICATED THE LLC IS CONSOLIDATED AND WELL DEFINED WITH 
ELEVATED WINDS UP TO 30KTS CONCENTRATED TO THE NORTH AND WESTERN 
QUADRANTS. UPPER LEVEL ANALYSIS REVEALS A FAVORABLE ENVIRONMENT WITH 
DIVERGENCE ALOFT AND POLEWARD AND WESTWARD OUTFLOW OFFSET BY LIGHT 
TO MODERATE (10-20KT) VERTICAL WIND SHEAR. SEA SURFACE TEMPERATURES 
AT 29-30C ARE ALSO FAVORABLE. DYNAMIC MODELS INDICATE 
INTENSIFICATION OVER THE NEXT 24 HOURS AS THE SYSTEM TRACKS WEST-
SOUTHWESTWARD. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 
TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1003 
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 
220200Z.
//
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