WDPN32 PGTW 200900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 10W (MINDULLE) WARNING NR 11// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 10W (MINDULLE), LOCATED APPROXIMATELY 152 NM SOUTH OF IWO TO, JAPAN, HAS TRACKED NORTHWARD AT 19 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS THE SYSTEM HAS MAINTAINED SYMMETRIC CONVECTION AND DEGREE OF WRAP INTO A LOW-LEVEL CIRCULATION CENTER. THE INITIAL POSITION IS BASED WITH HIGH CONFIDENCE ON A WELL-DEFINED LOW REFLECTIVITY CIRCULATION FEATURE IN THE 200511Z AMSU-B MICROWAVE IMAGE. THE INITIAL INTENSITY OS 55 KNOTS IS BASED ON DVORAK ESTIMATES. UPPER-LEVEL ANALYSIS INDICATE FAVORABLE CONDITIONS WITH A ROBUST POLEWARD OUTFLOW AND LOW (05-10 KNOT) VERTICAL WIND SHEAR. THE CYCLONE IS ON THE EASTERN EDGE OF A HIGH-LATITUDE MONSOON GYRE AND IS BEING STEERED NORTHWARD BY THE SOUTHERN EXTENSION OF THE SUBTROPICAL RIDGE (STR) ANCHORED EAST OF JAPAN. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 10W WILL CONTINUE ON A NORTHWARD TRACK UNDER THE INFLUENCE OF THE STR EXTENSION. STEADY INTENSIFICATION IS EXPECTED AS THE SYSTEM TRACKS OVER WARM WATERS (28 CELSIUS) AND UNDER FAVORABLE UPPER-LEVEL CONDITIONS, PEAKING AT 70 KNOTS AT TAU 36-48 PRIOR TO LANDFALL INTO THE ISLAND OF HONSHU NEAR TOKYO. A SLIGHT WESTWARD BEND IN THE TRACK IS EXPECTED BETWEEN TAU 12 AND 36 AS TS 10W INTERACTS WITH TS 12W (LIONROCK). AFTER LANDFALL, THE SYSTEM WILL BEGIN EXTRA-TROPICAL TRANSITION AND ACCELERATE NORTH-NORTHEASTWARD OVER HONSHU AS THE MAIN STR EAST OF JAPAN ASSUMES STEERING. C. IN THE EXTENDED TAUS, TS MINDULLE WILL CONTINUE TO ACCELERATE BUT TRACK MORE NORTHEASTWARD DEEPER INTO THE BAROCLINIC ZONE, BECOMING A GALE-FORCE LOW BY TAU 96. DYNAMIC MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT, HOWEVER, THERE SOME UNCERTAINTY IN THE MID PORTION OF THE TRACK FORECAST IN ANTICIPATION OF THE INTERACTION WITH TS 12W. IN VIEW OF THIS, THERE IS AN OVERALL FAIR CONFIDENCE TO THE JTWC TRACK FORECAST./=