MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 05W (JANGMI) WARNING NR 008// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 05W (JANGMI), LOCATED APPROXIMATELY 115 NM WEST- SOUTHWEST OF SASEBO, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT 30 KNOTS OVER THE PAST SIX HOURS. THE CURRENT POSITION IS SITUATED WITHIN AN EXPOSED LOW-LEVEL CIRCULATION CENTER, WITH HIGH CONFIDENCE. THE INTENSITY OF 40 KTS IS CONSISTENT WITH A CONSENSUS OF SUBJECTIVE DVORAK AND AUTOMATED INTENSITY ESTIMATES FROM MULTIPLE REPORTING AGENCIES. TS 05W IS TURNING NORTHEASTWARD AND ACCELERATING ALONG THE WESTERN PERIPHERY OF A SUBTROPICAL STEERING RIDGE (STR) TO THE EAST AND AHEAD OF AN APPROACHING MID-LATITUDE TROUGH TO THE NORTHWEST. THE SYSTEM IS PASSING THROUGH AN AREA OF MODERATE VERTICAL WIND SHEAR (15-20 KNOTS) AND WARM SEA SURFACE TEMPERATURES (28-29C). POLEWARD OUTFLOW ALOFT IS INCREASING AS THE SYSTEM BEGINS TO INTERACT WITH THE APPROACHING MIDLATITUDE TROUGH. MINIMAL DEEP CONVECTION REMAINS OVER THE CIRCULATION, PRIMARILY WITHIN THE SOUTHEASTERN QUADRANT. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 05W WILL CONTINUE TO TURN NORTHEASTWARD AS IT ROUNDS THE STR THROUGH THE 36 HOUR FORECAST PERIOD. STORM MOTION WILL REMAIN RAPID AS THE SYSTEM MERGES WITH THE APPROACHING MIDLATITUDE TROUGH AND TRANSITIONS INTO AN EXTRATROPICAL LOW BY TAU 24. INCREASING POLEWARD OUTFLOW ALOFT AND FAVORABLE BAROCLINIC INTERACTION WITH THE TROUGH WILL ALLOW TS 05W TO NEARLY MAINTAIN INTENSITY THROUGHOUT THE TRANSITION, DESPITE INCREASING VERTICAL WIND SHEAR AND PASSAGE OVER MUCH COOLER WATER. NUMERICAL MODEL SOLUTIONS REMAIN IN EXCELLENT AGREEMENT THROUGH THE FORECAST PERIOD, LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK.// NNNN NNNN