MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 19W (MITAG) WARNING NR 008// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 19W (MITAG), LOCATED APPROXIMATELY 479 NM SOUTH OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED WEST-NORTHWESTWARD AT 12 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL IMAGERY (MSI) SHOWS CONVECTIVE BANDING WRAPPING INTO A LOW LEVEL CIRCULATION CENTER (LLCC) PARTIALLY OBSCURED BY THE CIRRUS SHIELD, PLACING FAIR CONFIDENCE IN THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSESSED AT 55 KTS WITH GOOD CONFIDENCE, SUPPORTED BY MULTI-AGENCY DVORAK INTENSITY ESTIMATES OF T3.0/45KTS (PGTW) AND T3.5/55KTS (RCTP/RJTD) AS WELL AS A SATCON INTENSITY ESTIMATE OF 55 KTS. THE AFOREMENTIONED MSI DISPLAYED A LARGE AREA OF ASSOCIATED CONVECTION OFFSET TO THE SOUTH OF THE LLCC. UPPER LEVEL ANALYSIS REVEALS MODERATE (10-20 KTS) VERTICAL WIND SHEAR (VWS) AND EXCELLENT EQUATORWARD OUTFLOW. HOWEVER, AN AREA OF UPPER LEVEL CONVERGENCE TO THE NORTH OF THE LLCC IS LIMITING CONVECTION IN THAT REGION. AT 28- 29 CELSIUS, SEA SURFACE TEMPERATURE (SST) REMAINS FAVORABLE. OVERALL, THE ENVIRONMENT IS FAVORABLE FOR INTENSIFICATION. TS 19W IS UNDER THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE (STR) TO THE NORTHEAST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TRANSITING AROUND THE STR AXIS, THE FORECAST TRACK WILL GRADUALLY TURN NORTH-NORTHEASTWARD THROUGH TAU 72. BY TAU 48, AS THE SYSTEM CRESTS THE STR AXIS, FORECAST INTENSITY WILL PEAK AROUND 80 KTS. AFTER THAT, FRICTIONAL EFFECTS FROM LAND INTERACTION AND INCREASING VWS WILL SLOWLY WEAKEN TS 19W AS IT TRACKS ALONG THE COAST OF CHINA. MODEL GUIDANCE HAS COME INTO BETTER AGREEMENT IN THE LAST SIX HOURS, DECREASING CROSS-TRACK SPREAD AT TAU 72 TO 100 NM. JGSM REMAINS THE SOLE OUTLIER TO THE EAST. THE JTWC FORECAST TRACK IS PLACED NEAR MODEL CONSENSUS, LENDING FAIR CONFIDENCE TO THIS PORTION OF THE TRACK. C. AFTER TAU 72, TS 19W TURNS NORTHEASTWARD, BEGINS INTERACTING WITH THE MID-LATITUDE WESTERLIES, AND STARTS TO UNDERGO EXTRATROPICAL TRANSITION (ETT). DESPITE CONTINUED FAVORABLE UPPER LEVEL OUTFLOW, COOL SST, HIGH VWS, AND LAND INTERACTION WILL BEGIN TO ERODE TS 19W AS IT TRANSITS TOWARD THE KOREAN PENINSULA AND OVER THE SEA OF JAPAN. ETT IS EXPECTED TO BE COMPLETE BY TAU 120. ALL NUMERICAL MODELS SHOW A TIGHT ENVELOPE DURING THE RECURVE PORTION OF THIS FORECAST. HOWEVER, WITH SUFFICIENT DIFFERENCES IN THE TIMING OF THE RECURVE, CONFIDENCE IN THE JTWC FORECAST TRACK REMAINS FAIR.// NNNN NNNN