ABPW10 PGTW 081600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS REISSUED/081600Z-090600ZOCT2021//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/081351ZOCT2021//
REF/B/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/081521ZOCT2021//
NARR/REF A IS A TROPICAL CYCLONE WARNING. REF B IS A TROPICAL 
CYCLONE FORMATION ALERT.//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
   A. TROPICAL CYCLONE SUMMARY:
      (1) AT 08OCT21 1200Z, TROPICAL STORM 22W (LIONROCK) WAS 
LOCATED NEAR 19.0N 110.3E, APPROXIMATELY 276 NM EAST-SOUTHEAST OF 
HANOI, VIETNAM, AND HAD TRACKED NORTHWESTWARD AT 06 KNOTS OVER THE 
PAST SIX HOURS. MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 40 
KNOTS GUSTING TO 50 KNOTS. SEE REF A (WTPN31 PGTW 081500) FOR 
FURTHER DETAILS.
      (2) NO OTHER TROPICAL CYCLONES.
   B. TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED 
NEAR 12.4N 131.3E IS NOW LOCATED NEAR 12.6N 131.9E, APPROXIMATELY 
351NM NORTH-NORTHWEST OF PALAU. THIS SYSTEM IS CURRENTLY CLASSIFIED 
AS A MONSOON DEPRESSION WITH EXPANSIVE GALE-FORCE WINDS OVER THE 
EASTERN PERIPHERY OF THE SYSTEM. THE GALE-FORCE WINDS ARE LOCATED 
OVER 300NM FROM THE BROAD, POORLY-DEFINED SYSTEM CENTER. AS IS 
TYPICAL WITH MONSOON DEPRESSIONS, ANIMATED ENHANCED INFRARED 
SATELLITE IMAGERY AND A 080928Z SSMIS 91GHZ MICROWAVE IMAGE DEPICT 
EXTENSIVE AREAS OF INTENSE DEEP CONVECTION OVER THE WESTERN, 
SOUTHERN AND EASTERN PERIPHERIES WITH NO CENTRAL CONVECTION OVER THE 
BROAD, POORLY-DEFINED LOW-LEVEL CIRCULATION. A 081025Z ASCAT-A 
PARTIAL IMAGE REVEALS AN ELONGATED, WEAK CIRCULATION WITH 20-25 KNOT 
WESTERLY WINDS OVER THE SOUTHERN SEMICIRCLE AND SHARP TROUGHING 
EXTENDING NORTHEASTWARD INTO INVEST 94W, WHICH IS ROTATING AROUND 
THE PERIPHERY OF INVEST 93W. UPPER-LEVEL ANALYSIS INDICATES A 
MARGINAL ENVIRONMENT WITH CONVERGENT NORTHERLY FLOW OVER THE LLC AND 
LOW TO MODERATE (10-20 KTS) VERTICAL WIND SHEAR. GLOBAL MODELS 
INDICATE THAT THIS MONSOON DEPRESSION WILL STEADILY STRENGTHEN AS IT 
TRACKS NORTHWARD TO NORTHWESTWARD OVER THE NEXT TWO DAYS. THE SYSTEM 
IS EXPECTED TO GRADUALLY GAIN TROPICAL CYCLONE (WARM-CORE) 
CHARACTERISTICS WITH IMPROVED CENTRAL CONVECTION AND A RADIUS OF 
MAXIMUM WINDS LESS THAN 100NM. BASED ON THE PERIPHERAL WINDS IN 
RECENT ASCAT IMAGERY, MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED 
AT 30 TO 35 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE 
NEAR 996 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT 
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
      (2) THE AREA OF CONVECTION (INVEST 94W) PREVIOUSLY LOCATED 
NEAR 15.5N 137.7E IS NOW LOCATED NEAR 15.6N 137.1E, APPROXIMATELY  
460NM WEST-NORTHWEST OF GUAM. ANIMATED MULTISPECTRAL SATELLITE 
IMAGERY DEPICTS A BROAD, EXPOSED LOW-LEVEL CIRCULATION (LLC) WITH 
STRONG LOW-LEVEL CONVERGENCE FUELING EXTENSIVE DEEP CONVECTION OVER 
THE EASTERN SEMICIRCLE. RECENT MICROWAVE IMAGERY REVEALS STRONG 
CONVECTIVE BANDS OVER THE EASTERN AND SOUTHERN PERIPHERIES BUT 
LITTLE EVIDENCE OF A DISTINCT LLC. A 072318Z ASCAT-A IMAGE REVEALS 
SHARP TURNING WITH A SWATH OF 25-30 KNOT WINDS OVER THE EASTERN 
SEMICIRCLE BUT NO CLOSED CIRCULATION YET. GLOBAL MODELS INDICATE 
THAT INVEST 93W WILL MERGE WITH INVEST 94W OVER THE NEXT FEW DAYS. 
THERE IS SIGNIFICANT UNCERTAINTY IN HOW THESE TWO SYSTEMS WILL 
DEVELOP AND MERGE WITH HIGH UNCERTAINTY IN TRACK MOTION AS WELL.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 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 MEDIUM.
      (3) THE AREA OF CONVECTION (INVEST 95W) PREVIOUSLY LOCATED 
NEAR 14.5N 166.5E IS NOW LOCATED NEAR 14.8N 166.0E, APPROXIMATELY 
272NM SOUTH OF WAKE ISLAND. ANIMATED ENHANCED INFRARED SATELLITE 
IMAGERY DEPICTS A DISORGANIZED DISTURBANCE WITH WANING CONVECTION. A 
072253 ASCAT-B IMAGE SHOWS A TIGHTENING LOW LEVEL CIRCULATION WITH 
HIGHER WINDS (20 KNOTS) OFFSET OVER THE EASTERN SEMICIRCLE. 
ENVIRONMENTAL ANALYSIS INDICATES FAVORABLE CONDITIONS FOR 
DEVELOPMENT, WITH ROBUST POLEWARD OUTFLOW, ENHANCED BY UPPER LOWS TO 
THE NORTHWEST AND NORTHEAST, LOW (5-10 KTS) VERTICAL WIND SHEAR 
(VWS), AND WARM (30C) SEA SURFACE TEMPERATURES (SST). NUMERICAL 
MODELS ARE IN GENERAL AGREEMENT THAT INVEST 95W WILL TRACK WEST-
NORTHWESTWARD AND INTENSIFY OVER THE NEXT 24 TO 48 HOURS. MAXIMUM 
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15 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 MEDIUM.
      (4) 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.//
3. JUSTIFICATION FOR REISSUE:UPGRADED AREA IN 1.B.(1) TO HIGH.//
NNNN