ABPW10 PGTW 220600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS/220600Z-230600ZSEP2021//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/211221ZSEP2021//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.// 
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
   A. TROPICAL CYCLONE SUMMARY: NONE.
   B. TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION (INVEST 99W) PREVIOUSLY LOCATED 
NEAR 10.9N 150.8E IS NOW LOCATED NEAR 10.7N 150.1E, APPROXIMATELY 
355 NM EAST-SOUTHEAST OF GUAM. ANIMATED MULTI SPECTRAL IMAGERY (MSI) 
AND A 220305Z AMSR2 89GHZ PASS DEPICT POCKETS OF FLARING CONVECTION 
AROUND A LOW LEVEL CIRCULATION CENTER.  ENVIRONMENTAL ANALYSIS 
INDICATES A FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH A COMBINATION 
OF BOTH EQUATORWARD AND POLEWARD OUTFLOW, LOW (5-10 KT) VERTICAL 
WIND SHEAR (VWS) AND VERY WARM (30-31C) SEA SURFACE TEMPERATURES 
(SST). GLOBAL MODELS ARE IN GOOD AGREEMENT THAT INVEST 99W WILL 
CONTINUE TRACKING NORTHWESTWARD OVER THE NEXT 24-48 HOURS HOWEVER, 
THEY ARE SPLIT ON THE DEGREE OF DEVELOPMENT. GFS, ITS ENSEMBLE, AND 
NAVGEM ARE THE MOST AGGRESSIVE, INDICATING RAPID CONSOLIDATION AND 
INTENSIFICATION, WITH 99W DEVELOPING WITHIN THE NEXT 12-24 HOURS. 
ECMWF AND ITS ENSEMBLE ARE STILL MUCH MORE RESERVED, INDICATING 
LITTLE TO NO DEVELOPMENT UNTIL AFTER TAU 48, WELL TO THE WEST OF THE 
MARIANAS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1008 MB. 
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE 
WITHIN THE NEXT 24 HOURS REMAINS HIGH. SEE REF A (WTPN21 PGTW 
211230) FOR FURTHER DETAILS.
      (2) THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED 
NEAR 11.2N 116.4E IS NOW LOCATED NEAR 12.3N 115.6E, APPROXIMATELY 
242 NM NORTHWEST OF PUERTO PRINCESA, PHILIPPINES. ANIMATED MULTI 
SPECTRAL IMAGERY DEPICTS AN ILL-DEFINED AND BROAD LOW LEVEL 
CIRCULATION (LLC) WITH FLARING CONVECTION ALONG THE SOUTHWESTERN 
PERIPHERY. ENVIRONMENTAL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT 
FOR DEVELOPMENT WITH STRONG EQUATORWARD OUTFLOW ALOFT ACCOMPANIED BY 
LOW (10-15 KT) VERTICAL WIND SHEAR (VWS) AND WARM (29-30C) SEA 
SURFACE TEMPERATURES (SST). GLOBAL MODELS ARE IN AGREEMENT THAT 90W 
WILL TRACK WEST-NORTHWESTWARD TOWARDS VIETNAM AS IT STEADILY 
CONSOLIDATES. GFS, ECMWF AND NAVGEM ALL AGREE ON THE SYSTEM 
CONSOLIDATING AND STRENGTHENING TO NEAR TROPICAL DEPRESSION STRENGTH 
OVER THE NEXT 48 HOURS WITH THE GFS ENSEMBLE INDICATING SLIGHTLY 
HIGHER LEVEL OF DEVELOPMENT IN THE SOUTH CHINA SEA. MAXIMUM 
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA 
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1010 MB. THE POTENTIAL FOR 
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 
HOURS REMAINS LOW.
      (3) NO OTHER SUSPECT AREAS.
   C. SUBTROPICAL SYSTEM SUMMARY: NONE.
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
   A. TROPICAL CYCLONE SUMMARY: NONE.
   B. TROPICAL DISTURBANCE SUMMARY: NONE.
   C. SUBTROPICAL SYSTEM SUMMARY: NONE.//
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