WDIO31 PGTW 242100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03B (THREE) WARNING 
NR 
003//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 18.2N 90.2E
   INITIAL INTENSITY: 35 KTS
   GEOGRAPHIC REFERENCE: 283 NM SOUTH-SOUTHEAST OF KOLKATA, INDIA
   MOVEMENT PAST 6 HOURS: WESTWARD AT 08 KTS
   SIGNIFICANT WAVE HEIGHT: 13 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRA RED IMAGERY SHOW A CONSOLIDATING LOW LEVEL 
CIRCULATION CENTER (LLCC) AND DEEPENING CONVECTION AROUND THE CORE 
OF 
THE SYSTEM. THE BAY OF BENGAL IS SATURATED WITH DEEP MOISTURE BUT 
VERTICAL WINDSHEAR ALONG THE 20TH LATITUDE IS MARGINALY UNFAVORABLE 
FOR SYSTEM DEVELOPMENT. A 241910Z GMI PASS SHOWS DEEP CONVECTION 
OVER 
THE CORE ND CONSOLIDATING CONVECTIVE BANDS. THE INTENSITY ASSESSMENT 
IS BASED ON AN ADT VALUE OF 35KTS.

INITIAL WIND RADII BASIS: 241547Z METOP-C ASCAT.

CURRENT STEERING MECHANISM: THE WESTERN EXTENSION OF THE
SUBTROPICAL RIDGE OVER SOUTHEAST ASIA.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T2.0 - 30 KTS
   CIMSS SATCON: 36 KTS AT 241453Z
   CIMSS ADT: 35 KTS AT 241815Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY
UNFAVORABLE
   VWS: 15-20 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: WEAK POLEWARD

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TROPICAL CYCLONE 03B WILL SUSTAIN A STEADILY
WESTWARD TRACK AND INTENSIFY DUE TO WARM SEA SURFACE TEMPERATURES,
BUT 15-20KTS OF VERTICAL WINDSHEAR ALONG TRACK WILL IMPEDE
DEVELOPMENT. SCATTEROMETRY SHOWS THE SYSTEM IS SMALL AND TIGHTLY
ORGANIZED AND THEREFORE MAY BUFFER ITSELF FROM THE EXTERNAL
ENVIRONEMENT TO SOME EXTENT, BUT WATER VAPOR ANIMATION AND OCEAN
HEAT CONTENT VALUES INDICATE NO CONDITIONS EXIST FOR SUBSTANTIAL
INTENSIFICATION. VERTICAL WIND SHEAR IS HIGHER OFF THE EAST COAST
OF INDIA, THEREFORE THE SYSTEM WILL BEGINNING WEAKENING BEFORE
LANDFALL. 

MODEL DISCUSSION: BOTH TRACK AND INTENSITY GUIDANCE HAS HAS
TIGHTENED OVER THE PAST TWO CYCLES AND THERE IS NO GUIDANCE
INDICATING SUBSTANTIAL INTENSIFICATION.
THE JTWC TRACK FORECAST STAYS WITH THE MULTI-MODEL CONSENSUS AND
STAYS IN THE MIDDLE OF INTENSITY GUIDANCE.   

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: MEDIUM
   INTENSITY 0 - 72 HR: MEDIUM//
NNNN