ABIO10 PGTW 151330
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE INDIAN OCEAN
/REISSUED/151330Z-151800ZMAR2022//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/150751ZMAR2022//
AMPN/REF A IS A TROPICAL CYCLONE WARNING.//
RMKS/
1. NORTH INDIAN OCEAN AREA (MALAY PENINSULA WEST TO COAST OF AFRICA):
   A. TROPICAL CYCLONE SUMMARY: NONE.
   B. TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION (INVEST 91B) PREVIOUSLY LOCATED 
NEAR 2.1N 86.5E IS NOW LOCATED NEAR 3.3N 87.1E, APPROXIMATELY 480 NM 
EAST-SOUTHEAST OF COLOMBO, SRI LANKA. ANIMATED ENHANCED INFRARED 
SATELLITE IMAGERY DEPICTS LARGE, DISORGANIZED CLUSTERS OF DEEP 
CONVECTION FALRING OVER A BROAD LOW-LEVEL CIRCULATION. A 151046Z 
SSMIS 91GHZ COLOR COMPOSITE MICROWAVE IMAGE SHOWS A BROAD, WEAKLY 
DEFINED LOW-LEVEL CIRCULATION CENTER WITH POORLY-ORGANIZED DEEP 
CONVECTIVE ORGANIZATION. NUMERICAL MODELS INDICATE SLOW DEVELOPMENT 
OVER THE NEXT FEW DAYS AS THE DISTURBANCE TRACKS GENERALLY EASTWARD. 
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. 
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1006 MB. THE 
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE 
WITHIN THE NEXT 24 HOURS IS DOWNGRADED TO LOW.
      (2) NO OTHER SUSPECT AREAS.
   C. SUBTROPICAL SYSTEM SUMMARY: NONE.
2. SOUTH INDIAN OCEAN AREA (135E WEST TO COAST OF AFRICA):
   A. TROPICAL CYCLONE SUMMARY:
      (1) AT 15MAR22 0600Z, TROPICAL CYCLONE 20S (BILLY) WAS LOCATED 
NEAR 17.0S 97.2E, APPROXIMATELY 291 NM SOUTH OF THE COCOS ISLANDS, 
AUSTRALIA, AND HAD TRACKED WESTWARD AT 09 KNOTS OVER THE PAST SIX 
HOURS. MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 55 KNOTS 
GUSTING TO 70 KNOTS. SEE REF A (WTXS31 PGTW 150900) FOR FURTHER 
DETAILS.
      (2) NO OTHER TROPICAL CYCLONES.
   B. TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION (REMNANTS OF TC 19S) PREVIOUSLY 
LOCATED NEAR 15.3S 37.3E IS NOW LOCATED NEAR 18.5S 37.5E, 
APPROXIMATELY 195 NM WEST-NORTHWEST OF EUROPA ISLAND. ANIMATED 
MULTISPECTRAL SATELLITE IMAGERY INDICATES RAPIDLY WEAKENING 
CONVECTION WITH A THIN CANOPY OF CIRROSTRATUS CLOUDS OBSCURING THE 
LOW-LEVEL CIRCULATION CENTER (LLCC). A 151124Z AMSR2 89GHZ COLOR 
COMPOSITE MICROWAVE IMAGE DEPICTS VERY ISOLATED DEEP CONVECTION WITH 
SHALLOW BANDING WRAPPING INTO A DEFINED LLCC. A 150619Z ASCAT-B 
IMAGE SHOWS AN ELONGATED CIRCULATION WITH PREDOMINANTLY 15-25 KNOT 
WINDS EXCEPT FOR A SMALL PATCH OF 30-35 KNOT WINDS OVER THE EASTERN 
QUADRANT. UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT 
WITH AN ANTICYCLONE POSITIONED TO THE NORTHWEST AND FAIR EQUATORWARD 
AND POLEWARD OUTFLOW AS WELL AS LOW VERTICAL WIND SHEAR. THE PRIMARY 
LIMITING FACTOR IS PROXIMITY TO LAND. ECMWF INITIALIZES THIS SYSTEM 
BETTER THAN GFS AND MAINTAINS A QUASI-STATIONARY MOTION OVER THE 
NEXT DAY THEN A SLOW DRIFT INLAND OVER MOZAMBIQUE BY TAU 48 AT 
TROPICAL DEPRESSION STRENGTH. GFS IS NOT HANDLING THE SYSTEM WELL 
AND SHOWS A WEAK LOW PRESSURE AREA. MAXIMUM SUSTAINED SURFACE WINDS 
ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS 
ESTIMATED TO BE NEAR 1004 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A 
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS MEDIUM.
      (2) THE AREA OF CONVECTION (INVEST 91S) PREVIOUSLY LOCATED 
NEAR 12.1S 50.5E IS NOW LOCATED NEAR 12.5S 50.6E, APPROXIMATELY 346 
NM NORTH OF TOAMASINA, MADAGASCAR. ANIMATED MULTISPECTRAL SATELLITE 
IMAGERY DEPICTS A FULLY-EXPOSED, WELL-DEFINED LOW-LEVEL CIRCULATION 
CENTER (LLCC) WITH DISORGANIZED, FLARING CONVECTION. A 150945Z AMSR2 
89GHZ COLOR COMPOSITE MICROWAVE IMAGE SHOWS FRAGMENTED, SHALLOW 
BANDING WRAPPING INTO THE DEFINED LLCC. A 150617Z ASCAT-B IMAGE 
REVEALS AN ELONGATED, WEAK CIRCULATION WITH 15 TO 20 KNOT WINDS. 
UPPER-LEVEL ANALYSIS INDICATES A MARGINAL ENVIRONMENT WITH MODERATE 
TO HIGH (20-25 KNOTS) VERTICAL WIND SHEAR AND WEAKLY DIFFLUENT FLOW 
ALOFT. SST VALUES ARE CONDUCIVE AT 28C. NUMERICAL MODEL GUIDANCE 
INDICATES THE SYSTEM WILL TRACK SOUTHWARD ALONG THE EAST COAST OF 
MADAGASCAR THEN TRACK OVER NORTHERN MADAGASCAR BETWEEN TAU 24 TO TAU 
36 WITH NO SIGNIFICANT DEVELOPMENT EXPECTED. MAXIMUM SUSTAINED 
SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL 
PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. THE POTENTIAL FOR THE 
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 
HOURS IS DOWNGRADED TO LOW.
      (3) NO OTHER SUSPECT AREAS.
   C. SUBTROPICAL SYSTEM SUMMARY: NONE.
3. JUSTIFICATION FOR REISSUE: DOWNGRADED AREAS IN PARA. 1.B.(1) AND 
PARA. 2.B.(2) TO LOW. UPDATED PARA. 2.A.(1) AND PARA. 2.B.(1).//
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