WDPN32 PGTW 060300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 13W (KUJIRA) WARNING NR 006// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 17.4N 120.7E INITIAL INTENSITY: 30 KTS GEOGRAPHIC REFERENCE: 169 NM NORTH OF MANILA, PHILIPPINES MOVEMENT PAST 6 HOURS: EAST-SOUTHEASTWARD AT 06 KTS SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TROPICAL DEPRESSION (TD) 13W HAS LIKELY MADE LANDFALL OVER THE WESTERN COAST OF LUZON. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS DISORGANIZED CONVECTIVE BANDING THAT IS OBSCURING A WEAK, COMPACT LOW-LEVEL CIRCULATION CENTER (LLCC). WHILE THE SYSTEM IS IN AN AREA OF MODERATE VERTICAL WIND SHEAR (VWS) AND MODEST DIVERGENCE ALOFT, THE INTERACTION WITH RUGGED TERRAIN IS THE PREDOMINANTLY AND HIGHLY UNFAVORABLE FACTOR DRIVING ITS STRUCTURE. THE INITIAL POSITION IS ASSESSED WITH LOW CONFIDENCE. THE INITIAL INTENSITY HAS BEEN LOWERED TO 30 KTS WITH MEDIUM CONFIDENCE BASED ON THE STANDARD DECAY RATE OVER LAND. IT IS UNCLEAR IF THE LLCC HAS REMAINED INTACT THROUGH THE LAND INTERACTION. INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND RADII). CURRENT STEERING MECHANISM: EXTENSIVE LOWER-LEVEL SOUTHWESTERLY MONSOONAL SURGE FLOW AGENCY DVORAK AND AUTOMATED FIXES: PGTW: NO CURRENT ESTIMATE RJTD: T1.5 - 25 KTS CIMSS D-MINT: 38 KTS AT 052332Z CIMSS D-PRINT: 35 KTS AT 060010Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY UNFAVORABLE VWS: 15-20 KTS SST: 29-30 CELSIUS OUTFLOW: MODERATE EQUATORWARD OTHER FACTORS: LAND INTERACTION ANALYSIS CONFIDENCE: INITIAL POSITION: LOW INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: NOT APPLICABLE 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TD 13W WILL BE CARRIED EAST-NORTHEASTWARD BY DEEP-LAYER WESTERLIES EXTENDING FROM THE SURFACE TO 400 MB. WHAT REMAINS OF THE SYSTEM WILL EMERGE OVER THE EASTERN COAST OF LUZON AND THE PHILIPPINE SEA WITHIN THE NEXT 12 HOURS, WITH THIS MOTION CONTINUING UNTIL COMPLETE DISSIPATION. IT IS QUITE POSSIBLE THAT THE CIRCULATION WILL NOT SURVIVE ITS JOURNEY OVER THE MOUNTAINOUS TERRAIN OF NORTHERN LUZON. IN FACT, MODELS GENERALLY SUPPORT THIS SCENARIO, DEPICTING AN OPEN TROUGH EMERGING FROM THE EASTERN COAST RATHER THAN A CLOSED CIRCULATION. THE ENVIRONMENT WILL BE UNFAVORABLE, CHARACTERIZED BY WARM SEA SURFACE TEMPERATURE (SST) STRONGLY OFFSET BY MODERATE TO HIGH VWS. THE 25-KT TROUGH WILL GRADUALLY BROADEN AND BECOME ABSORBED BY THE LARGE CIRCULATION OF TYPHOON 12W TO THE NORTH. THE FORECAST GENEROUSLY MAINTAINS THE SYSTEM FOR 48 HOURS BEFORE DEPICTING FULL DISSIPATION. IT IS POSSIBLE THAT SUBSEQUENT FORECASTS MAY BE CUT SHORT IF NO EVIDENCE OF A CLOSED CIRCULATION CAN BE FOUND WHEN IT RE-EMERGES OVER WATER. MODEL DISCUSSION: THE MODEL TRACKERS ARE IN GOOD AGREEMENT IN AN EASTWARD TO EAST-NORTHEASTWARD MOTION THROUGH TAU 36. THE ECMWF SOLUTION BOUNDS THE EQUATORWARD SIDE OF THE UNCERTAINTY ENVELOPE, WHILE THE REMAINING MODELS ARE TIGHTLY CLUSTERED. THE JTWC TRACK FORECAST IS POSITIONED NEAR THE CONSENSUS WITH HIGH CONFIDENCE. THE JTWC INTENSITY FORECAST DEPICTS CONTINUED WEAKENING OVER THE NEXT 12 HOURS DUE TO ONGOING LAND INTERACTION. THE RELIABLE INTENSITY AIDS ARE FLAT, SHOWING MINIMAL STRENGTHENING OR WEAKENING, LARGELY BECAUSE THE SYSTEM WILL REMAIN DEEPLY EMBEDDED WITHIN THE 25-30 KT SOUTHWESTERLY FLOW. DEGENERATION INTO A TROUGH WITH 25 KT WINDS CONFINED TO THE SOUTHERN PERIPHERY IS PREDICTED NO LATER THAN TAU 36. FORECAST CONFIDENCE: TRACK 00-72 HR: HIGH TRACK 72-120 HR: --- INTENSITY 00-72 HR: MEDIUM INTENSITY 72-120 HR: ---// NNNN