The tropical system designated at 19S by the JTWC and the NRL, and once declared dissipated, has started to regenerate, prompting the issuance of a TCFA (Tropical Cyclone formation Alert) by the JTWC, as of 2030UTC, 08 May, 2012. The TCFA text reads as follows:
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 110 NM EITHER SIDE OF A LINE FROM 8.6S 129.6E TO 11.6S 126.0E 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 28 TO 32 KNOTS. METSAT IMAGERY AT 081732Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 9.4S 128.9E. THE SYSTEM IS MOVING SOUTHWESTWARD AT 05 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (REMNANTS OF TC 19S) PREVIOUSLY LOCATED NEAR 9.0S 129.2E IS NOW LOCATED NEAR 9.4S 128.9E, APPROXIMATELY 215 NM NORTH-NORTHWEST OF DARWIN, AUSTRALIA. ANIMATED INFRARED SATELLITE IMAGERY REVEALS BANDING CONVECTION PERSISTING OVER THE PAST 12 HOURS, WITH A DEVELOPING LOW LEVEL CIRCULATION CENTER (LLCC). A 081540Z OSCAT PASS INDICATED WINDS BETWEEN 20 TO 25 KNOTS ALONG THE SOUTHERN PERIPHERY WITH STRONGER WINDS (30 KNOTS) FURTHER TO THE SOUTH. UPPER LEVEL ANALYSIS INDICATES THE LLCC REMAINS EQUATORWARD OF A SUBTROPICAL RIDGE AXIS WITH LOW TO MODERATE LEVELS OF VERTICAL WIND SHEAR (VWS) (10 TO 15 KNOTS) ENHANCING POLEWARD VENTILATION. AS THE LLCC APPROACHES THE RIDGE AXIS, DECREASING VWS AND INCREASING VENTILATION WILL LIKELY CAUSE THE REMNANTS OF TC 19S TO REGENERATE WITHIN THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 28 TO 32 KNOTS, BASED ON AN IMPROVING CONVECTIVE SIGNATURE IN THE ANIMATED INFRARED IMAGERY. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. BASED ON THE DEEP BANDING CONVECTION PERSISTING, GOOD POLEWARD OUTFLOW AND FAVORABLE SURFACE CONDITIONS, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
Below is the TCFA graphic, and satellite image, as provided by the JTWC:
Whereas most of us, including the official forecasting agencies, thought this system was finished due to the shearing it underwent on 06-07 May, 2012, it would appear that regeneration is once again taking place. Interests in the southern hemisphere including those located in Indonesia and Australia.
Michael E. Williams, 0000UTC