WDPN32 PGTW 232100 COR
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 05W (GAEMI) WARNING NR 
017A CORRECTED//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 22.8N 123.5E
   INITIAL INTENSITY: 120 KTS
   GEOGRAPHIC REFERENCE: 176 NM SOUTHEAST OF TAIPEI, TAIWAN
   MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 13 KTS
   SIGNIFICANT WAVE HEIGHT: 34 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS 
TYPHOON (TY) 05W GAEMI WITH A DISTINCT PINHOLE EYE AND A LARGE
REGION OF DEEP CONVECTION LOCATED TO THE SOUTH AND SOUTHWEST DUE TO
MODERATE (10-15KT) VERTICAL WIND SHEAR (VWS) FROM THE NORTH, GIVING
THE SYSTEM AN ASYMMETRIC APPEARANCE ON THE UPPER-LEVELS. RADAR
IMAGERY INDICATES THAT THE SYSTEM IS UNDERGOING AN EYEWALL
REPLACEMENT CYCLE (ERC) WITH A CONCENTRIC RING OF CONVECTION
DEVELOPING AROUND THE INNER EYE. A 231433Z GMI 89GHZ IMAGE DEPICTS
A MICROWAVE EYE HINTING AT THE EARLY DEVELOPMENT OF AN OUTER
EYEWALL AS WELL. THE INITIAL POSITION IS PLACED WITH HIGH
CONFIDENCE BASED ON THE AFOREMENTIONED ANIMATED EIR, MICROWAVE, AND
RADAR IMAGERY. THE INITIAL INTENSITY OF 120 KTS IS ASSESSED WITH
MEDIUM CONFIDENCE BASED ON THE AGENCY AND OBJECTIVE FIXES LISTED
BELOW.

INITIAL WIND RADII BASIS: PERSISTENCE 

CURRENT STEERING MECHANISM: ON THE WESTERN PERIPHERY OF A
SUBTROPICAL RIDGE (STR) TO THE EAST.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T6.5 - 127 KTS
   RJTD: T5.5 - 102 KTS
   RCTP: T6.0 - 115 KTS
   KNES: T6.0 - 115 KTS
   DEMS: T5.5 - 102 KTS
   CIMSS SATCON: 105 KTS AT 1900Z
   CIMSS ADT: 84 KTS AT 1900Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 5-10 KTS
   SST: 30-31 CELSIUS
   OUTFLOW: STRONG RADIAL

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   INITIAL INTENSITY: MEDIUM
   INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TY 05W IS FORECAST TO HAVE AN OVERALL TRACK
DIRECTION TO THE NORTHWEST THROUGH THE END OF THE FORECAST PERIOD
WHILE UNDER THE INFLUENCE OF THE STR TO THE EAST. HISTORICALLY, THE
TOPOGRAPHY OF NORTHERN TAIWAN IS KNOWN TO CAUSE A TRACK DEFLECTION
WHICH MAY CAUSE A TRACK DISCONTINUITY AROUND THE NORTHERN COAST THAT 
WOULD OCCUR BETWEEN TAU 12 AND 24 AND IS NOT CAPTURED IN THE FORECAST 
GRAPHIC. BETWEEN TAU 36-48, TY 05W WILL MAKE LANDFALL IN MAINLAND 
CHINA AND COME UNDER THE INFLUENCE OF SOUTHWESTERLY FLOW, TRACKING 
SLIGHTLY NORTH-NORTHWEST BY THE END OF THE FORECAST PERIOD. THE 
SYSTEM WILL REMAIN IN A HIGHLY FAVORABLE ENVIRONMENT FOR 
INTENSIFICATION FOR THE NEXT 12 HOURS. AFTER COMPLETING ERC WHICH 
WILL CAUSE A SLIGHT WEAKENING BEFORE THE SYSTEM CONTINUES TO 
INTENSIFY TO A PEAK OF 130KTS BY TAU 12 IN AN ENVIRONMENT OF LOW 
SHEAR, STRONG UPPER-LEVEL DIVERGENCE, HIGH SEA SURFACE TEMPERATURES 
AND OCEAN HEAT CONTENT. OUTFLOW WILL REMAIN STRONG EQUATORWARD WHILE 
A TUTT CELL LOCATED WEST WILL CONTINUE TO ENCOURAGE STRONG POLEWARD 
OUTFLOW. UPON INTERACTION WITH LAND, TY 05W WILL BEGIN WEAKENING 
WHILE UNDER THE INFLUENCE OF SIGNIFICANT SHEAR (20-30KTS) OVER LAND 
AND IN THE TAIWAN STRAIT BEFORE REACHING FULL DISSIPATION OVER LAND. 
THERE MAY BE VARIATIONS IN HOW RAPIDLY WEAKENING WILL OCCUR BASED ON 
IF AND HOW LARGE THE TRACK DEVIATIONS ARE AROUND THE NORTHERN PORTION 
OF TAIWAN.

MODEL DISCUSSION: DETERMINISTIC MODEL GUIDANCE IS IN GOOD AGREEMENT
THAT TY 05W WILL TRACK NORTHWEST THROUGH THE END OF THE FORECAST
PERIOD PRIOR TO LANDFALL. HOWEVER, MESOSCALE MODELS HAFS-A AND HWRF
DEPICT THAT THE SYSTEM WILL DEFLECT NORTHWARD UPON LANDFALL WITH
TAIWAN RATHER THAN RESUME THE PREVIOUS TRACK AND HINTS AT A MORE
NORTHWARD LANDFALL IN MAINLAND CHINA. THE JTWC INTENSITY GUIDANCE
IS ALSO IN GOOD AGREEMENT THAT THE SYSTEM WILL INTENSIFY OVER THE
NEXT 24 HOURS BEFORE CONTINUOUSLY WEAKENING TO DISSIPATION THROUGH
TAU 96.

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: HIGH
   TRACK 72-120 HR: HIGH
   INTENSITY 0 - 72 HR: MEDIUM
   INTENSITY 72-120 HR: LOW

2. JUSTIFICATION FOR CORRECTION: INITIAL PROGNOSTIC REASONING 
REFERRED TO TYPHOON 05W (GAEMI) AS SUPER TYPHOON BUT DOES NOT HAVE AN 
INTENSITY GREATER THAN 130KTS. CORRECTED GRAMMATICAL ERROR PERTAINING 
TO LANDFALL AND PEAK INTENSITY IN THE FORECAST DISCUSSION.//
NNNN