WDIO31 PGTW 240300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03B (DANA) WARNING NR 004// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 18.8N 88.4E INITIAL INTENSITY: 60 KTS GEOGRAPHIC REFERENCE: 228 NM SOUTH OF KOLKATA, INDIA MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 08 KTS SIGNIFICANT WAVE HEIGHT: 24 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS EXTENSIVE DEEP CONVECTIVE PERSISTING OVER AND TO THE SOUTHWEST OF A LOW-LEVEL CIRCULATION CENTER EVIDENT IN RECENT MICROWAVE IMAGERY INCLUDING A 240019Z SSMIS PASS. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON 37 GHZ IMAGERY FROM A 232158Z SSMIS PASS AND A 232330Z PGTW SATELLITE FIX POSITION. THE INITIAL INTENSITY OF 60 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON A CONSENSUS OF SUBJECTIVE DVORAK AND AUTOMATED INTENSITY ESTIMATES FROM VARIOUS REPORTING AGENCIES. A COMPARISON OF LOWER AND HIGHER FREQUENCY MICROWAVE SATELLITE IMAGERY SUGGESTS A SOUTHWESTWARD TILT OF THE SYSTEM WITH HEIGHT UNDER THE INFLUENCE OF EASTERLY VERTICAL WIND SHEAR. INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) TO THE NORTH AND EAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.5 - 55 KTS KNES: T3.5 - 55 KTS CIMSS ADT: 63 KTS AT 240000Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 15-20 KTS SST: 29-30 CELSIUS OUTFLOW: STRONG POLEWARD AND EQUATORWARD ANALYSIS CONFIDENCE: INITIAL POSITION: MEDIUM INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: FORECAST TRACK SPEEDS HAVE INCREASED A BIT FROM THE PREVIOUS WARNING. OTHERWISE, THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 03B IS EXPECTED TO CONTINUE TRACKING STEADILY NORTH-NORTHWESTWARD OVER THE NEXT 36 HOURS UNDER THE INFLUENCE OF THE CURRENT STEERING RIDGE, MAKING LANDFALL ALONG THE INDIAN COAST AROUND TAU 36. THEREAFTER, A BUILDING SUBTROPICAL RIDGE TO THE NORTHWEST WILL EXERT AN INCREASING INFLUENCE ON THE SYSTEM AND STEERING INLAND ON A WEST-SOUTHWESTWARD TRAJECTORY. NEAR-TERM INTENSIFICATION IS EXPECTED AS THE SYSTEM PASSES OVER WARM WATER AND UPPER-LEVEL OUTFLOW REMAINS FAVORABLE. HOWEVER, PERSISTENT EASTERLY FLOW ALOFT SHOULD PREVENT THE SYSTEM FROM RAPIDLY INTENSIFYING. BY TAU 24, LAND INTERACTION WILL REVERSE THE INTENSIFICATION TREND WITH DISSIPATION EXPECTED BY TAU 72. MODEL DISCUSSION: NUMERICAL MODELS ARE IN GOOD AGREEMENT REGARDING THE OVERALL STEERING SCENARIO AND INTENSITY TREND, BUT THERE IS PRONOUNCED TRACK SPREAD ASSOCIATED WITH THE TIMING OF THE STEERING TRANSITION AND TURN TO THE WEST-SOUTHWEST LATER IN THE FORECAST PERIOD. THE MODEL GUIDANCE IS BRACKETED BY NAVGEM TO THE SOUTH AND THE GEFS ENSEMBLE MEAN TO THE NORTH WITH AN 85 NM SPREAD IN THE EVENTUAL LANDFALL POSITION. THE AIDS ARE FAIRLY EVENLY DISTRIBUTED BETWEEN THESE SOLUTIONS, SO THE CURRENT JTWC FORECAST STAYS THE COURSE LARGELY CONSISTENT WITH PREVIOUS WARNINGS AND THE MULTI-MODEL CONSENSUS. THE INTENSITY FORECAST IS LARGELY CONSISTENT WITH THE NUMERICAL GUIDANCE, HEDGED SLIGHTLY HIGHER IN THE NEAR-TERM GIVEN MOSTLY FAVORABLE ENVIRONMENTAL CONDITIONS AND RECENT TRENDS. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM// NNNN