WDXS31 PGTW 132100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 07S (DIKELEDI) WARNING NR 009// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 15.5S 40.2E INITIAL INTENSITY: 70 KTS GEOGRAPHIC REFERENCE: 61 NM SOUTH-SOUTHWEST OF NACALA, MOZAMBIQUE MOVEMENT PAST 6 HOURS: SOUTHWESTWARD AT 05 KTS SIGNIFICANT WAVE HEIGHT: OVER LAND SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TROPICAL CYCLONE 07S (DIKELEDI) AS A VERY COMPACT SYSTEM JUST ONSHORE OF THE COAST OF MOZAMBIQUE. AN EYE BREIFLY APPEARED AROUND 131200Z AS 07S MADE LANDFALL NEAR THE TOWN OF CALAJULO. THE CENTRAL CONVECTION HAS QUICKLY ERODED SINCE MAKING LANDFALL, INITIATING A BRIEF RAPID WEAKENING TREND. ENVIRONMENTAL ANALYSIS INDICATES THAT 07S IS IN AN UNFAVORABLE ENVIRONMENT CHARACTERIZED BY STRONG EQUATORWARD OUTFLOW ALOFT AND LOW (10-15 KTS) VERTICAL WIND SHEAR, GREATLY OFFSET BY THE TERRAIN INTERACTION. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE ANIMATED EIR AND A 131828Z GMI 37 GHZ MICROWAVE IMAGE SHOWING THE LOW-LEVEL STRUCTURE. THE INITIAL INTENSITY OF 70 KTS IS ASSESSED WITH LOW CONFIDENCE BASED ON SPARSE CIMSS INTENSITY ESTIMATES LISTED BELOW AND THE WEAKENING TREND OVER LAND. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: NORTHWESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) POSITIONED TO THE SOUTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: NO CURRENT ESTIMATE CIMSS DPRINT: 61 KTS AT 131730Z CIMSS MW SOUNDERS: 79 KTS AT 131638Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE VWS: 10-15 KTS SST: OVER LAND OUTFLOW: STRONG EQUATORWARD OTHER FACTORS: TERRAIN INTERACTION WITH MOZAMBIQUE ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: LOW INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: 07S IS FORECAST TO TRACK SOUTHWARD, ALONG THE WESTERN PERIPHERY OF THE STR TO THE SOUTHEAST THROUGH TAU 48. AFTER TAU 48, 07S WILL BEGIN TO TRACK MORE SOUTHEASTWARD AS IT ROUNDS THE RIDGE AXIS AND HEADS TOWARD THE BAROCLINIC ZONE AND UPPER-LEVEL JET. EXTRATROPICAL TRANSITION IS FORECAST TO BEGIN AROUND TAU 96 WITH COMPLETION AROUND TAU 120, AS IT BECOMES EMBEDDED WITHIN THE STRONG UPPER-LEVEL WESTERLIES. REGARDING INTENSITY, 07S IS FORECAST TO CONTINUE WEAKENING OVER THE NEXT 12 HOURS AS IT CONTINUES TO TRAVERSE OVER EASTERN MOZAMBIQUE. AFTER TAU 12, TERRAIN INTERACTION WILL CEASE AND THE ENVIRONMENT WILL BECOME MUCH MORE FAVORABLE. LOW VERTICAL WIND SHEAR, WARM SEA SURFACE TEMPERATURES, AND IMPROVING POLEWARD OUTFLOW ALOFT WILL ALLOW THE SYSTEM TO INTENSIFY TO AROUND 90 KTS AT TAU 48. A PEAK INTENSITY MAY OCCUR NEAR TAU 60 (NOT PICTURED IN WARNING GRAPHIC DUE TO TEMPORAL LIMITATIONS). STARTING AT TAU 72, VERTICAL WIND SHEAR BEGINS TO RISE OVER 20 KTS AND SEA SURFACE TEMPERATURES START TO DROP. THIS WILL CAUSE 07S TO WEAKEN THROUGHOUT THE REMAINDER OF THE FORECAST PERIOD AS CONDITIONS WILL ONLY WORSEN. INTENSITY IS EXPECTED TO BE AROUND 45 KTS AS THE SYSTEM FULLY TRANSITIONS INTO AN EXTRATROPICAL CYCLONE. MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT REGARDING THE TRACK OF 07S THOUGH TAU 72 WITH A 70 NM CROSS-TRACK SPREAD AT THAT TIME. AFTER TAU 72, ALONG TRACK SPREAD INCREASES DUE TO DIFFERENCES IN HOW THE VORTEX INTERACTS WITH THE JET. THE JTWC TRACK FORECAST IS PLACED CLOSE TO CONSENSUS WITH HIGH CONFIDENCE THROUGH TAU 72 AND MEDIUM CONFIDENCE THEREAFTER. INTENSITY GUIDANCE IS IN MODERATE AGREEMENT WITH A SPLIT BETWEEN THE MESOSCALE MODELS AND GLOBAL MODELS. MESOSCALE MODELS SUGGEST THE INTENSIFICATION TREND THOUGH TAU 60. HWRF IS THE MOST AGGRESSIVE, WITH A PEAK INTENSITY OF AROUND 115 KTS WHILE HAFS-A AND COAMPS-TC SUGGEST A PEAK OF 90-95 KTS. GFS DIFFERS CONSIDERABLY WITH A 60 KNOT INTENSITY THROUGH TAU 96. THE JTWC INTENSITY FORECAST IS PLACED CLOSER TO THE MESOSCALE MODELS DUE TO THE EXPECTED FAVORABLE ENVIRONMENT WITH OVERALL MEDIUM CONFIDENCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: MEDIUM// NNNN