ABIO10 PGTW 171800
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE INDIAN OCEAN/171800Z-
181800ZAPR2025//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/171351ZAPR2025//
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: NONE.
   C. SUBTROPICAL SYSTEM SUMMARY: NONE.
2. SOUTH INDIAN OCEAN AREA (135E WEST TO COAST OF AFRICA):
   A. TROPICAL CYCLONE SUMMARY:
      (1) AT 17APR25 1200Z, TROPICAL CYCLONE 29S (ERROL) WAS LOCATED 
NEAR 15.4S 120.3E, APPROXIMATELY 186 NM NORTHWEST OF BROOME, AUSTRALIA, 
AND HAD TRACKED EAST-SOUTHEASTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. 
MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 80 KNOTS GUSTING TO 
100 KNOTS. SEE REF A (WTXS31 PGTW 171500) FOR FURTHER DETAILS.
      (2) NO OTHER TROPICAL CYCLONES.
   B. TROPICAL DISTURBANCE SUMMARY:
      (1) AN AREA OF CONVECTION (INVEST 99S) HAS PERSISTED NEAR 13.0S 
71.7E, APPROXIMATELY 338 NM SOUTH OF DIEGO GARCIA. ANIMATED ENHANCED 
INFRARED (EIR) SATELLITE IMAGERY DEPICT A POORLY ORGANIZED LOW LEVEL 
CIRCULATION CENTER (LLCC) WITH A BROAD AREA OF FLARING 
CONVECTION WITHIN THE SOUTHEASTERN QUADRANT. A 171611Z ASCAT-B IMAGE 
EMPHASIZES A BROAD WEAK CIRCULATION AT THE SURFACE. ENVIRONMENTAL 
ANALYSIS REVEALS A MARGINALLY FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH 
MODERATE TO HIGH (20-25 KNOTS) VERTICAL WIND SHEAR, GOOD POLEWARD UPPER-
LEVEL OUTFLOW, AND WARM (28-29 C) SEA SURFACE TEMPERATURES. 
DETERMINISTIC AND ENSEMBLE MODELS ARE IN FAIR AGREEMENT, SHOWING GRADUAL 
INTENSIFICATION IN THE SOUTH INDIAN OCEAN OVER THE NEXT 48 HOURS. 
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 KNOTS. MINIMUM 
SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. THE POTENTIAL FOR 
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 
HOURS IS LOW.
      (2) NO OTHER SUSPECT AREAS.
   C. SUBTROPICAL SYSTEM SUMMARY: NONE.//
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