WDPN32 PGTW 300900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 23W (KONG-REY) WARNING NR 022// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 19.8N 124.2E INITIAL INTENSITY: 125 KTS GEOGRAPHIC REFERENCE: 351 NM SOUTH-SOUTHEAST OF TAIPEI, TAIWAN MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 10 KTS SIGNIFICANT WAVE HEIGHT: 47 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TYPHOON (TY) 23W (KONG-REY), SLIGHTLY WEAKER BUT STILL IMPRESSIVE, CONTINUES TO TRACK NORTHWESTWARD TOWARDS TAIWAN. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A PICTURESQUE STORM WITH A LARGE EYE, AND MULTIPLE IMPRESSIVE MESOVORTICES RAPIDLY SPINNING ALONG THE INSIDE EDGE OF THE EYEWALL. THE HIGH-RESOLUTION MSI ALSO SHOWS A DEVELOPING WEDGE OF RELATIVELY DRIER LOW- TO MID-LEVEL AIR BEGINNING TO FORM INTO A DISTINCT MOAT, ALREADY EXTENDING FROM THE NORTH COUNTERCLOCKWISE TO THE SOUTHEAST OF THE CIRCULATION. THIS IS SUPPORTED BY A BEAUTIFUL 300457Z AMSR2 MICROWAVE PASS, WHICH REVEALED A PERFECTLY CIRCULAR AND DENSE INNER EYEWALL, ALMOST COMPLETELY CUTOFF FROM A SECONDARY EYEWALL AND SEPARATED BY A WELL-DEFINED MOAT. THESE FEATURES SHOW UP IN BOTH THE 89GHZ AND 37GHZ BAND, PROVIDING EXTREMELY HIGH CONFIDENCE TO THE STRUCTURAL ANALYSIS. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE AND PLACED IN THE CENTER OF THE LARGE EYE, SUPPORTED BY EXTRAPOLATION OF THE 37GHZ MICROWAVE EYE IN THE AMSR2 IMAGE NOTED ABOVE. CIMSS ADT OUTPUT AND ANALYSIS OF CLOUD TOP TEMPERATURES INDICATE THE CLOUD TOPS HAVE WARMED 6C SINCE 300000Z AND 10C SINCE 292100Z, SUGGESTING THAT BASED ON THAT ALONE, THE SYSTEM HAS STARTED TO WEAKEN. ADDITIONALLY, SUBJECTIVE AGENCY DVORAK FINAL-T NUMBERS HAVE STARTED TO COME DOWN SHARPLY, THOUGH THE CURRENT INTENSITY VALUES REMAIN AT T6.5-T7.0 DUE TO CONSTRAINTS. THE SAME CAN BE SAID FOR THE ADJUSTED AND RAW ADT VALUES, WHICH ARE DOWN TO LESS THAN T6.0. ALL THAT TO SAY, THE SYSTEM HAS STARTED TO WEAKEN DUE TO THE ONSET OF THE ERC, AND THE INITIAL INTENSITY HAS BEEN LOWERED TO 125 KNOTS, WITH MEDIUM CONFIDENCE. THE ENVIRONMENT REMAINS FAVORABLE OVERALL, HOWEVER THE ONSET OF ERC AND AN SOME STRONGER NORTHEASTERLY SHEAR (INDICATED AS 16 KTS IN THE LATEST CIMSS ANALYSIS) ARE GOING TO OFFSET THE OTHERWISE FAVORABLE CONDITIONS. INITIAL WIND RADII BASIS: SCATTEROMETER DATA CURRENT STEERING MECHANISM: SOUTHWESTERN PERIPHERY OF A DEEP-LAYER SUBTROPICAL RIDGE (STR) CENTERED TO THE NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T7.0 - 140 KTS RJTD: T6.5 - 127 KTS RCTP: T6.5 - 127 KTS KNES: T7.0 - 140 KTS CIMSS SATCON: 129 KTS AT 300514Z CIMSS ADT: 127 KTS AT 300530Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 15-20 KTS SST: 28-29 CELSIUS OUTFLOW: STRONG RADIAL OTHER FACTORS: STRONG POLEWARD OUTFLOW INTO THE BASE OF AN UPPER-LEVEL TROF. ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: HIGH 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: THERE IS NO SIGNIFICANT CHANGE IN THE TRACK FORECAST, WHICH REMAINS CONSISTENT WITH THE LAST SEVERAL FORECASTS. THE SYSTEM WILL CONTINUE TO TRACK NORTHWESTWARD ALONG THE SOUTHWESTERN SIDE OF THE STEERING RIDGE FOR THE NEXT 36 HOURS OR SO. BETWEEN NOW AND LANDFALL, TY 23W IS FORECAST TO WEAKEN STEADILY DUE MAINLY TO THE ERC. THE FACT THAT THE SYSTEM IS ALREADY QUITE LARGE SUGGESTS THAT IT IS UNLIKELY TO COMPLETE A FULL ERC OR REINTENSIFY PRIOR TO LANDFALL. WHILE NOT EXPLICITLY CAPTURED IN THE FORECAST, AS THE SYSTEM APPROACHES THE EASTERN COAST OF TAIWAN, TRACK MOTION IS VERY LIKELY TO BECOME ERRATIC, WITH POTENTIAL SIGNIFICANT CHANGES IN TRACK SPEED AND DIRECTION WHICH COULD DELAY LANDFALL AND PASSAGE OVER THE CENTRAL MOUNTAIN RANGE (CMR). THE SYSTEM IS LIKELY TO BECOME DECOUPLED AS IT ATTEMPTS TO CROSS OVER THE HIGHEST PEAKS OF THE CMR, AND A LEE-SIDE JUMP AND VORTICITY BUILD-DOWN ON THE WESTERN SIDE OF THE ISLAND VERY LIKELY. BY TAU 36, THE SYSTEM IS EXPECTED TO BE REFORMING ON THE WESTERN COAST OF TAIWAN AND MOVING INTO THE TAIWAN STRAIT TO THE WEST OF TAIPEI, HAVING STARTED TO ROUND THE RIDGE AXIS SIMULTANEOUS TO CROSSING THE CMR. WHILE THE CENTER OF THE SYSTEM IS CURRENTLY EXPECTED TO REMAIN OVER WATER, THE ANTICIPATED VORTEX DECOUPLING, HIGH VWS, AND DRY AIR FLOWING IN FROM EASTERN CHINA, MEAN THAT THE SYSTEM WILL RAPIDLY WEAKEN AFTER IT MOVES BACK OVER WATER. AT THE SAME TIME, THE SYSTEM WILL COMMENCE EXTRATROPICAL TRANSITION (ETT) AS IT MOVES INTO THE EAST CHINA SEA (ECS), AROUND TAU 48. BY TAU 72, THE SYSTEM WILL HAVE ROUNDED THE RIDGE AXIS AND BE ACCELERATING TOWARDS THE EAST-NORTHEAST ALONG A DEVELOPING FRONTAL BOUNDARY. FULL TRANSITION INTO A GALE-FORCE EXTRATROPICAL LOW IS EXPECTED SHORTLY AFTER TAU 72, BUT THE FORECAST IS EXTENDED TO TAU 96 TO CAPTURE THE FULL TRANSITION PHASE. MODEL DISCUSSION: DETERMINISTIC TRACK GUIDANCE IS IN VERY GOOD AGREEMENT, WITH JUST A 35NM SPREAD AT LANDFALL, INCREASING TO 60NM AT TAU 48. AFTER THIS POINT, AS THE SYSTEM ROUNDS THE RIDGE, BOTH CROSS- AND ALONG-TRACK SPREAD INCREASE SIGNIFICANTLY AND SHARPLY. BY TAU 72 THE CROSS-TRACK SPREAD INCREASES TO ABOUT 150NM BUT ALONG-TRACK SPREAD POPS UP TO 575NM, AS THE ECMWF DROPS THE VORTEX BY TAU 72, WHILE THE EGRR RACES IT AHEAD TO A POINT SOUTH OF KYOTO. THIS TREND ONLY INCREASES BY TAU 96, WITH ALONG-TRACK SPREAD UP TO NEARLY 1000NM BY THE END OF THE FORECAST PERIOD. THE JTWC FORECAST IS LAID NEAR THE CONSENSUS MEAN UP TO TAU 48, THEN CLOSEST TO THE GFS DETERMINISTIC TRACKER THEREAFTER. INTENSITY GUIDANCE IS IN GOOD AGREEMENT WITH MINIMAL SPREAD AMONGST THE RELIABLE GUIDANCE MEMBERS. THE JTWC FORECAST LIES CLOSE TO THE CONSENSUS MEAN THROUGH THE FORECAST PERIOD. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72-120 HR: LOW INTENSITY 0 - 72 HR: HIGH INTENSITY 72-120 HR: MEDIUM// NNNN