ABIO10 PGTW 040330 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE INDIAN OCEAN /REISSUED/040330Z-041800ZMAR2021// REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/040152ZMAR2021// REF/B/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/040251ZMAR2021// NARR/REF A IS A TROPICAL CYCLONE WARNING. REF B IS A TROPICAL /CYCLONE FORMATION ALERT.// RMKS/ 1. NORTH INDIAN OCEAN AREA (MALAY PENINSULA WEST TO COAST OF AFRICA): A. TROPICAL CYCLONE SUMMARY: NONE. B. TROPICAL DISTURBANCE SUMMARY: NONE. C. SUBTROPICAL SYSTEM SUMMARY: NONE. 2. SOUTH INDIAN OCEAN AREA (135E WEST TO COAST OF AFRICA): A. TROPICAL CYCLONE SUMMARY: (1) AT 04MAR21 0000Z, TROPICAL CYCLONE 22S (MARIAN) WAS LOCATED NEAR 20.6S 93.2E, APPROXIMATELY 550 NM SOUTH-SOUTHWEST OF THE COCOS ISLANDS, AUSTRALIA, AND HAD TRACKED SOUTH-SOUTHEASTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 55 KNOTS GUSTING TO 70 KNOTS. SEE REF A (WTXS31 PGTW 040300) FOR FURTHER DETAILS. (2) NO OTHER TROPICAL CYCLONES. B. TROPICAL DISTURBANCE SUMMARY: (1) THE AREA OF CONVECTION (INVEST 90S) PREVIOUSLY LOCATED NEAR 15.6S 67.4E IS NOW LOCATED NEAR 16.0S 69.5E, APPROXIMATELY 543 NM SOUTH-SOUTHWEST OF DIEGO GARCIA. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY AND A 032043Z AMSR2 89 GHZ MICROWAVE IMAGE DEPICT FORMATIVE BANDING WRAPPING INTO AN CONSOLIDATING LOW LEVEL CIRCULATION CENTER (LLCC) WITH FLARING CONVECTION IN THE NORTHERN AND EASTERN SEMICIRCLES. INVEST 90S IS IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH GOOD OUTFLOW ALOFT, LOW (<15KTS) VERTICAL WIND SHEAR (VWS) AND WARM (29-30C) SEA SURFACE TEMPERATURES. GLOBAL MODELS ARE IN GENERAL AGREEMENT THAT INVEST 90S WILL TRACK EAST- SOUTHEASTWARD AS IT CONSOLIDATES. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO HIGH. SEE REF B (WTXS21 PGTW 040300) FOR FURTHER DETAILS. (2) NO OTHER SUSPECT AREAS. C. SUBTROPICAL SYSTEM SUMMARY: NONE. 3. JUSTIFICATION FOR REISSUE: UPGRADED AREA IN PARA 2.B.(1) TO HIGH.// NNNN