MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 23W (MARIA) WARNING NR 03// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 23W (MARIA), LOCATED APPROXIMATELY 390 NM SOUTH OF IWO TO, JAPAN, HAS TRACKED NORTH-NORTHWESTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY (EIR) SHOWS CENTRALIZED BANDING IS BEGINNING TO IMPROVE ALONG THE SOUTHERN PERIPHERY BUT REMAINS STRAINED ALONG THE NORTHERN HALF OF THE SYSTEM DUE TO OUTFLOW FROM TY 22W IN THE NORTHWESTERN QUADRANT. THE CURRENT POSITION IS BASED ON THE EIR LOOP WITH A POSITION FIX FROM PGTW. THE CURRENT INTENSITY OF 35 KNOTS WAS BASED ON A 2.5/2.5 DVORAK ESTIMATE FROM PGTW. UPPER LEVEL ANALYSIS INDICATES THE LLCC IS SOUTH OF THE RIDGE AXIS IN A REGION OF MODERATE (10 TO 20 KNOTS) VERTICAL WIND SHEAR (VWS) WITH FAVORABLE EQUATORWARD OUTFLOW. THE CYCLONE IS TRACKING ALONG THE SOUTHWEST EXTENSION OF A BUILDING 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. TS 23W IS EXPECTED TO TRACK NORTHWESTWARD OVER THE NEXT 12 HOURS WITH THE POSSIBILITY OF MODERATE DUAL CYCLONE INTERACTION WITH TY 22W BETWEEN TAU 24 TO 36. DUE TO THE QUICK TRACK SPEED THE INTERACTION WILL BE LIMITED AS TS 23W ROUNDS THE STR AXIS AND BEGINS TRACKING NORTHEASTWARD BEYOND TAU 48. THE SYSTEM WILL SEE WEAK INTENSIFICATION AS POLEWARD OUTFLOW WILL BE SUPPRESSED BY TY 22W TO THE NORTHWEST. BEFORE TAU 72, THE SYSTEM WILL BEGIN TO ERODE DUE TO INCREASING VWS AND COOLING SEA SURFACE TEMPERATURES. C. AFTER TAU 72, TS 23W WILL ACCELERATE NORTHEASTWARD THEN BEGIN EXTRA-TROPICAL TRANSITION BY TAU 96. THE SYSTEM WILL BECOME A COLD CORE LOW BY END OF FORECAST. THE LIMITED NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT THROUGH TAU 36 BUT HAVE SLIGHT DIFFERENCES IN THE RECURVATURE SCENARIO AND THE SPEED OF THE SYSTEM AFTER MOVING NORTH OF THE STR AXIS. THERE IS LOW CONFIDENCE IN THE TRACK FORECAST DUE TO THE UNCERTAINTY OF THE INTERACTION WITH TY 22W AND THE MODEL VARIANCE.// NNNN NNNN