MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 34W (MAN-YI) WARNING NR 15// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 34W (MAN-YI), LOCATED APPROXIMATELY 796 NM SOUTHEAST OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED NORTHWESTWARD AT 13 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A LARGE AREA OF DEEP CONVECTION OBSCURING THE LOW- LEVEL CIRCULATION CENTER (LLCC), HOWEVER, A 230407Z AMSR2 36GHZ IMAGE SHOWS TIGHTLY-CURVED CONVECTIVE BANDING WRAPPING INTO A WELL- DEFINED MICROWAVE EYE FEATURE, WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE. THE INITIAL INTENSITY REMAINS ASSESSED AT 90 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T5.0 (90 KNOTS) FROM ALL AGENCIES. UPPER-LEVEL ANALYSIS INDICATES LOW VERTICAL WIND SHEAR AND ROBUST POLEWARD OUTFLOW ENHANCED BY STRONG WESTERLIES TO THE NORTH. TY 34W IS TRACKING ALONG THE WESTERN PERIPHERY OF A DEEP- LAYERED SUBTROPICAL RIDGE (STR) POSITIONED TO THE EAST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY 34W IS FORECAST TO TRACK POLEWARD THROUGH TAU 24, HOWEVER, THE SYSTEM IS FORECAST TO SLOW SIGNIFICANTLY AND TURN WEST- NORTHWESTWARD TO NORTHWESTWARD THROUGH TAU 72 AS A STRONG, BROAD HIGH PRESSURE SYSTEM BUILDS SOUTH OF JAPAN. LOW-LEVEL NORTHEASTERLY FLOW ASSOCIATED WITH THIS HIGH IS FORECAST TO ADVECT COOLER, MORE STABLE AIR INTO THE SYSTEM, WHICH WILL RESULT IN A SHARP WEAKENING TREND. DUE TO THE COMPLEX, QUICKLY-EVOLVING SYNOPTIC ENVIRONMENT, THE NUMERICAL MODEL GUIDANCE DIVERGES AFTER TAU 24 WITH A 276NM SPREAD IN SOLUTIONS AT TAU 72. C. AFTER TAU 72, NUMERICAL MODEL GUIDANCE CONTINUES TO DIVERGE WITH A 651NM SPREAD IN SOLUTIONS AT TAU 120. ADDITIONALLY, HIGH UNCERTAINTY ASSOCIATED WITH INCONSISTENT MODEL FORECASTS, WHICH NOW INDICATE A RECURVE TRACK/WEAK EXTRATROPICAL TRANSITION (ETT), REFLECT A CHALLENGING FORECAST SCENARIO. ALTHOUGH TY 34W WILL BEGIN ETT NEAR TAU 96 AS IT BEGINS TO INTERACT WITH THE MIDLATITUDE WESTERLIES AND A STRONG BAROCLINIC ZONE, TY 34W IS NOT FORECAST TO COMPLETE ETT DUE TO STRONG VERTICAL WIND SHEAR AND ENTRAINMENT OF COOLER, MORE STABLE AIR. THEREFORE, THE JTWC FORECAST CONTINUES TO FAVOR A DISSIPATION SCENARIO. DUE TO THE COMPLEX, EVOLVING SCENARIO, THERE IS LOW CONFIDENCE (HIGH UNCERTAINTY) IN THE JTWC TRACK FORECAST, WHICH IS POSITIONED NEAR BUT SLOWER THAN THE MULTI-MODEL CONSENSUS.// NNNN NNNN