Tropical Cyclone Formation Alert issued for Invest 97S, 30/03utc

JTWC IS ISSUING 3HOURLY SATELLITE BULLETINS ON INVEST 97S.

THE AREA OF CONVECTION (INVEST 97S) PREVIOUSLY LOCATED NEAR 16.6S 142.6E IS NOW LOCATED NEAR 17.2S 147.3E, APPROXIMATELY 170KM EAST-SOUTHEAST OF CAIRNS, AUSTRALIA. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND ANIMATED RADAR IMAGERY FROM THE CAIRNS RADAR DEPICT A CONSOLIDATING SYSTEM WITH IMPROVED CONVECTIVE BANDING WRAPPING INTO A BROAD LOW-LEVEL CIRCULATION CENTER (LLCC). A 292044Z SSMIS 37GHZ MICROWAVE IMAGE INDICATES DISORGANIZED LOW-LEVEL BANDING WITH A WEAKLY-DEFINED LLCC. A RECENT SCATTEROMETER IMAGE REVEALS AN ELONGATED CIRCULATION WITH 25 TO 30 KNOT WINDS. THIS SYSTEM IS A HYBRID SYSTEM WITH BOTH SUBTROPICAL AND TROPICAL CHARACTERISTICS, AND IS LOCATED JUST NORTH OF A SUBTROPICAL JET. UPPER-LEVEL FEATURE TRACK WINDS INDICATE A DEVELOPING ANTICYCLONE OVER THE SYSTEM WITH IMPROVED EQUATORWARD AND POLEWARD OUTFLOW. ADDITIONALLY, VERTICAL WIND SHEAR (VWS) HAS DECREASED FROM MODERATE TO LOW (10-15 KNOTS) OVER THE PAST 12 HOURS. SEA SURFACE TEMPERATURES ARE CONDUCIVE AT 30- 31C. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN MARGINALLY- FAVORABLE FOR ABOUT 24 TO 36 HOURS AS THE SYSTEM TRACKS EAST- SOUTHEASTWARD, WHICH MAY ALLOW FOR FURTHER CONSOLIDATION. AFTER THIS SHORT WINDOW, THE SYSTEM WILL TRACK SOUTHEASTWARD UNDER INCREASING VWS (30-40 KNOTS) WITH SLIGHTLY COOLER SST VALUES, AND IS FORECASTED TO TRANSITION TO A SUBTROPICAL GALE-FORCE LOW AFTER 48H. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1000 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO HIGH.