Update: Possible Cyclone Formation Alert: Madagascar

Image: NOAA19 13h15 SAST  (Nic Cronje, Nelspruit) Click on image for larger view.

Image: NOAA15 16H28 SAST (Ben Engelbrecht, Dundee) Click on image for larger view.

WTXS21 PGTW 270130
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/260121Z FEB 12//
AMPN/REF IS TROPICAL CYCLONE FORMATION ALERT (WTXS21 PGTW 260130)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 180 NM EITHER SIDE OF A LINE FROM 13.3S 49.4E TO 15.0S 43.0E 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 27 TO 32 KNOTS. METSAT IMAGERY AT 270100Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 13.5S 48.5E. THE SYSTEM IS MOVING WESTWARD AT 09 KNOTS. 2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.0S 49.8E, IS NOW LOCATED NEAR 13.5S 48.5E, APPROXIMATELY 345 NM NORTH-NORTHEAST OF ANTANANARIVO, MADAGASCAR. ANIMATED INFRARED SATELLITE IMAGERY INDICATES THAT THE SYSTEM HAS WEAKENED DUE TO LAND INTERACTION AND PERSISTENT EASTERLY VERTICAL WIND SHEAR (VWS); HOWEVER, THE LOW-LEVEL CIRCULATION CENTER (LLCC) IS NOW RE-EMERGING OVER WATER AND IS EXPECTED TO RAPIDLY RE-DEVELOP OVER THE NEXT 24 HOURS. A 262245Z AMSU IMAGE SHOWS THAT DEEP CONVECTIVE BANDING HAS BECOME FRAGMENTED WHILE LOW-LEVEL BANDING REMAINS TIGHTLY WRAPPED. RECENT SURFACE OBSERVATIONS AT FMNN, LOCATED APPROXIMATELY 20 NM NNW OF THE CENTER, SHOW SLP VALUES NEAR 998 MB. UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH DIFFLUENT EASTERLY FLOW AND GOOD POLEWARD AND EQUATORWARD OUTFLOW. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 27 TO 32 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 REMAINS HIGH.

- JTWC