MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 13W (SOUDELOR) WARNING NR 23// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUPER TYPHOON (STY) 13W (SOUDELOR), LOCATED APPROXIMATELY 630 NM SOUTHEAST OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED WEST-NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. RECENT ANIMATED EIR SATELLITE SHOWS THE SYSTEM HAS MAINTAINED A SYMMETRIC SIGNATURE EVEN AS CONVECTIVE BANDS ARE WRAPPING LOOSER INTO A SHARPLY-OUTLINED 15-NM DIAMETER EYE. ADDITIONALLY, SUBSIDENCE ALONG THE NORTHWEST PERIPHERY IS HAMPERING FURTHER DEVELOPMENT. THE INITIAL POSITION IS BASED ON THE EYE FEATURE IN THE EIR LOOP WITH HIGH CONFIDENCE. THE INITIAL INTENSITY OF 130 KNOTS IS BASED ON CONGRUENT AND CONCENTRIC DVORAK FIXES FROM PGTW AND RJTD AND REFLECTS THE WEAKENED STATE OF THE SYSTEM. UPPER- LEVEL ANALYSIS INDICATES STY 13W IS LOCATED IN AN AREA OF LOW VWS AND GOOD DIFFLUENCE ALOFT WITH A STRONG EQUATORWARD BIAS. HOWEVER, A TUTT IS CAUSING SUBSIDENCE ALONG THE NORTHWEST PERIPHERY. STY SOUDELOR IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED STR TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. STY 13W WILL REMAIN ON A WEST-NORTHWESTWARD TRAJECTORY UP TO TAU 72 UNDER THE STEERING INFLUENCE OF THE STR. SOUDELOR IS EXPECTED TO GRADUALLY WEAKEN OVER THE NEXT 36 HOURS DUE TO THE SUBSIDING EFFECT OF THE AFOREMENTIONED TUTT. AFTERWARDS, THE DIMINISHING EFFECT OF THE TUTT PLUS CONTINUED LIGHT VWS, GOOD OUTFLOW, AND WARM SSTS WILL REINVIGORATE THE CYCLONE TO A SECONDARY PEAK OF 125 KNOTS BY TAU 72. C. IN THE EXTENDED TAUS, STY SOUDELOR WILL TRACK ACROSS NORTHERN TAIWAN, THE TAIWAN STRAIT, THEN MAKE LANDFALL INTO CHINA NEAR FUZHOU. AFTERWARDS, A MIGRATORY MID-LATITUDE TROUGH PASSING TO THE NORTH WILL WEAKEN THE STR AND DRIVE THE CYCLONE MORE NORTHWESTWARD. DEGRADED ENVIRONMENTAL CONDITIONS AND LAND INTERACTION WILL WEAKEN AND ERODE THE SYSTEM ANEW - REDUCING IT TO 45 KNOTS BY END OF FORECAST. DYNAMIC MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT THROUGHOUT THE FORECAST PERIOD, LENDING HIGH CONFIDENCE IN THE JTWC TRACK FORECAST.// NNNN NNNN