Typhoon 26W(TORAJI) intensifying and bearing down on LUZON// 1015utc

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON 24W, 25W , 26W AND INVEST 94W.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: AS INDICATED ON ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY, EASTERLY VERTICAL WIND SHEAR (VWS) HAS DECREASED OVER THE PAST SIX HOURS, WITH THE CENTRAL DENSE OVERCAST BECOMING MORE SYMMETRIC AND BUILDING BACK OVER THE LOW-LEVEL CIRCULATION CENTER (LLCC). CONSEQUENTLY, AGENCY SUBJECTIVE DVORAK ESTIMATES INCREASED TO 77 KNOTS AND CIMSS OBJECTIVE INTENSITY ESTIMATES NOW RANGE FROM 71 TO 74 KNOTS. ADDITIONALLY, A 100924Z SSMIS 91GHZ COLOR COMPOSITE MICROWAVE IMAGE SHOWS IMPROVED CONVECTIVE STRUCTURE, WITH A PARTIAL INNER EYEWALL AND A DEFINED LLCC IN ADDITION TO TIGHTLY CURVED BANDING OVER ALL QUADRANTS. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE SSMIS IMAGE AND RECENT ASCAT DATA. ENVIRONMENTAL CONDITIONS ARE HIGHLY FAVORABLE WITH STRONG RADIAL OUTFLOW AND VERY HIGH OCEAN HEAT CONTENT VALUES AIDING IN SUSTAINED INTENSIFICATION.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TYPHOON (TY) 26W IS EXPECTED TO TRACK WEST- NORTHWESTWARD THROUGH TAU 12 WITH A SHORT PERIOD OF RAPID INTENSIFICATION EXPECTED AS VWS RELAXES. PEAK INTENSITY SHOULD BE NEAR 85 KNOTS BUT COULD POTENTIALLY JUMP HIGHER IF THE SYSTEM FORMS AN EYE. AFTER LANDFALL NEAR TAU 12, THE SYSTEM WILL WEAKEN SIGNIFICANTLY WHILE CROSSING THE MOUNTAINOUS REGION OF LUZON. AFTER TAU 24, TY 26W WILL TRACK WEST-NORTHWESTWARD THROUGH TAU 72 WITH STEADY WEAKENING DUE TO DRY AIR ENTRAINMENT AND COOLING SST VALUES, PARTICULARLY AFTER TAU 48. IN THE EXTENDED PERIOD, THE SYSTEM WILL SLOW AS THE STR WEAKENS, THEN WEAKEN QUICKLY AND TURN WESTWARD UNDER LOW-LEVEL STEERING. THERE IS INCREASING UNCERTAINTY IN BOTH THE TRACK AND INTENSITY FORECAST AFTER TAU 72, WITH SOME POTENTIAL FOR A STRONGER THAN EXPECTED SYSTEM, WHICH COULD LEAD TO A MORE WEST- NORTHWESTWARD TRACK INTO SOUTHERN CHINA.

MODEL DISCUSSION: THE 100600Z ECMWF ENSEMBLE (EPS) REVEALS A TIGHT GROUPING OF SOLUTIONS THROUGH TAU 72, WITH INCREASING UNCERTAINTY AFTER TAU 72. THE 100600Z GFS ENSEMBLE (GEFS) IS ALSO IN TIGHT AGREEMENT THROUGH TAU 72. AFTER TAU 72, BOTH ENSEMBLES DIVERGE WITH SOLUTIONS SPREAD FROM SOUTH OF HAINAN ISLAND TO HONG KONG. THIS PRONOUNCED UNCERTAINTY AFTER TAU 72 IS ASSOCIATED WITH A WEAKENING STR OVER THE HONG KONG, HAINAN ISLAND REGION DUE TO ENCROACHING WESTERLIES OVER SOUTHEAST CHINA. A STRONG SYSTEM WOULD BE MORE LIKELY TO TRACK WEST-NORTHWESTWARD WHILE A WEAKER SYSTEM WILL TURN WESTWARD TO SOUTHWESTWARD UNDER THE LOW-LEVEL STEERING FLOW. WITH THE EXCEPTION OF NAVGEM, WHICH SHARPLY RECURVES THE SYSTEM POLEWARD TOWARD TAIWAN, THE DETERMINISTIC GUIDANCE SHOWS A SIMILAR SPREAD OF SOLUTIONS AFTER TAU 72.