WDPN31 PGTW 310300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 29W (KROSA) WARNING NR 09// RMKS// 1. FOR METEOROLOGISTS 2. 6-HOUR SUMMARY AND ANALYSIS: TYPHOON (TY) 29W (KROSA), LOCATED APPROXIMATELY 262 NM NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-NORTHWESTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) INDICATES A TIGHTLY-CURVED BANDING WRAPPING INTO A WELL- DEFINED LOW-LEVEL CIRCULATION CENTER WITH A POSSIBLE DEVELOPING EYE. A 302334Z SSMIS 91GHZ IMAGE DEPICTS A NEAR-COMPLETE EYEWALL WITH A GAP IN THE EASTERN QUADRANT AND A 37GHZ MICROWAVE EYE FEATURE, WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 80 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF 77 KNOTS FROM BOTH KNES AND PGTW AS WELL AS A SATCON ESTIMATE OF 79 KNOTS. OVERALL, THE UPPER-LEVEL ENVIRONMENT CONTINUES TO BE FAVORABLE FOR FURTHER DEVELOPMENT WITH NEAR-RADIAL OUTFLOW; HOWEVER, THE OUTER BANDING SHOULD START TO INTERACT WITH LUZON WITHIN THE NEXT 03 TO 06 HOURS. TY 29W IS TRACKING WESTWARD ALONG THE SOUTHWEST PERIPHERY OF THE MID-LEVEL SUBTROPICAL RIDGE (STR). THE 30/12Z 500MB ANALYSIS INDICATES A BREAK IN THE STR POSITIONED JUST SOUTH OF TAIWAN; HOWEVER, THE STR APPEARS TO BE MAINTANING TO THE NORTH OF THE SYSTEM (EASTERN STR) AND OVER THE NORTHERN SOUTH CHINA SEA (WESTERN STR) DESPITE THE PRESENCE OF THE LONGWAVE TROUGH OVER ASIA. 3. FORECAST REASONING: A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY 29W IS FORECAST TO TRACK WEST-NORTHWESTWARD ALONG THE SOUTHWESTERN PERIPHERY OF THE STR, TOWARD THE AFOREMENTIONED BREAK IN THE STR NEAR TAIWAN. DYNAMIC MODEL GUIDANCE INDICATES A WEST-NORTHWESTWARD TRACK THROUGH TAU 72 WITH DECREASING TRACK SPEEDS AS THE SYSTEM BEGINS TO TRANSITION TO THE STEERING INFLUENCE OF THE WESTERN STR. THERE IS A 210 NM SPREAD IN MODEL SOLUTIONS AT TAU 72 WITH UNCERTAINTY IN THE AMOUNT OF POLEWARD TRACK PRIOR TO THE TURN SOUTHWESTWARD. IN GENERAL, THE DYNAMIC MODELS ARE SPLIT INTO TWO DISTINCT GROUPINGS WITH JGSM, JENS AND EGRR INDICATING A FLATTER TRACK AND A SHARPER TURN SOUTHWESTWARD AND GFDN, ECMWF, NAVGEM AND GFS INDICATING A MORE WEST-NORTHWESTWARD TRACK THROUGH TAU 72. THE JTWC FORECAST CONTINUES TO FAVOR THE NORTHERN GROUPING OF MODELS AND, THEREFORE, IS POSITIONED NORTH OF THE MULTI- MODEL CONSENSUS. TY 29W IS EXPECTED TO PEAK AT 90 KNOTS PRIOR TO LANDFALL, WEAKEN SLIGHTLY AS IT SKIRTS NORTHERN LUZON THEN RE- INTENSIFY AS IT EMERGES OVER THE SOUTH CHINA SEA. C. IN THE EXTENDED TAUS, TY 29W WILL TURN SHARPLY SOUTHWESTWARD AS IT TRACKS UNDER THE WESTERN STR AND WILL WEAKEN AS IT INTERACTS WITH HAINAN ISLAND AND ENCOUNTERS COOLER SST AND INCREASING VERTICAL WIND SHEAR. DYNAMIC GUIDANCE IS IN AGREEMENT ON THE SOUTHWESTWARD TURN; HOWEVER, CONTINUES TO SHOW A LARGE DIFFERENCE IN THE EXACT TRACK, THEREFORE, THERE IS LOW OVERALL CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN