WWDIO31 PGTW 241500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03B (THREE) WARNING NR 002// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 18.6N 90.8E INITIAL INTENSITY: 35 KTS GEOGRAPHIC REFERENCE: 275 NM SOUTH-SOUTHEAST OF KOLKATA, INDIA MOVEMENT PAST 6 HOURS: WESTWARD AT 12 KTS SIGNIFICANT WAVE HEIGHT: 12 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON A 241238Z SSMIS MICROWAVE IMAGE SHOWING DEEP CONVECTION WRAPPED AROUND THE LLCC. THE INITIAL INTENSITY OF 35 KNOTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON AGENCY AND AUTOMATED DVORAK INTENSITY ESTIMATES. THE ENVIRONMENT IS OVERALL MARGINALLY FAVORABLE WITH LOW VERTICAL WIND SHEAR AND WARM SEA SURFACE TEMPERATURES DESPITE WEAKENING OUTFLOW ALOFT. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE TO THE NORTH AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.0 - 30 KTS CIMSS ADT: 35 KTS AT 241210Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE VWS: 10-15 KTS SST: 28-29 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: TC 03B WILL GENERALLY CONTINUE ON ITS CURRENT WESTWARD TRACK UNTIL DISSIPATION OVER INDIA BEFORE TAU 72. THE FAVORABLE ENVIRONMENT OF SUSTAINED WARM SEA SURFACE TEMPERATURES (28- 29 DEGREES CELSIUS), WEAK UPPER LEVEL DIVERGENCE AND LOW SHEAR (10- 15 KNOTS) WILL FUEL GRADUAL INTENSIFICATION TO A PEAK OF 50 KNOTS BY TAU 48. A SLIGHT WEAKENING IS EXPECTED BEFORE LANDFALL DUE TO MODERATE SHEAR. AFTERWARDS, LAND INTERACTION ACROSS THE RUGGED TERRAIN OF INDIA WILL CAUSE RAPID WEAKENING. MODEL DISCUSSION: NUMERICAL MODELS HAVE SLIGHTLY IMPROVED, WITH A TRACK SPREAD OF 190NM AT TAU 48. THE JTWC TRACK IS LAID NEAR TRACK CONSENSUS. THE ENVIRONMENT IS MARGINALLY FAVORABLE FOR CONTINUED INTENSIFICATION, HOWEVER, THERE IS A SIGNIFICANT UNCERTAINTY IN THE CURRENT INTENSITY GUIDANCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM// NNNN