MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 27W (KALMAEGI) WARNING NR 022// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 27W (KALMAEGI), LOCATED APPROXIMATELY 222 NM NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED NORTHWESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS THE SYSTEM CONTINUED TO SLOWLY CONSOLIDATE AS THE RAIN BANDS WRAPPED TIGHTER INTO THE LOW LEVEL CIRCULATION (LLC) THAT IS OBSCURED BY A DEEPENING CENTRAL CONVECTION WITH OVERSHOOTING CLOUD TOPS. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON A DEFINED LLC IN THE 172251Z SSMIS 37GHZ COLORIZED IMAGE. THE INITIAL INTENSITY OF 60KTS IS BASED ON AN OVERALL ASSESSMENT OF OBJECTIVE AND AGENCY DVORAK ESTIMATES, INCLUDING A T2.5/35KTS FROM RJTD, T3.5/55KTS FROM RCTP, T4.0/65KTS FROM PGTW, AND 50KTS FROM SATCON. ANALYSES INDICATE A MARGINALLY FAVORABLE ENVIRONMENT WITH MODERATE (15-20KT) RELATIVE VERTICAL WIND SHEAR (VWS) AND COOL/DRY NORTHERLY WIND SURGE OVER THE PHILIPPINE SEA OFFSET BY A VIGOROUS POLEWARD OUTFLOW AND WARM (29C) SSTS. THE CYCLONE IS TRACKING ALONG THE WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR) TO THE EAST- NORTHEAST. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS KALMAEGI WILL CONTINUE NORTHWESTWARD TOWARD LUZON STRAIT UP TO TAU 24 UNDER THE STR TO THE EAST-NORTHEAST. AFTERWARD, ANOTHER STR TO THE WEST-NORTHWEST WILL BUILD, REORIENT NORTHWARD, AND DRIVE THE CYCLONE SOUTHWESTWARD, MAKING LANDFALL OVER THE NORTHERN TIP OF LUZON NEAR APARRI SHORTLY AFTER TAU 24, DRAG ACROSS THE RUGGED INTERIOR BEFORE EXITING INTO THE SOUTH CHINA SEA NEAR VIGAN JUST AFTER TAU 36. THE MARGINALLY FAVORABLE ENVIRONMENT WILL INTENSIFY THE SYSTEM TO A PEAK OF 65KTS AT TAUS 12 TO 24 BEFORE LANDFALL. AFTERWARD, INCREASING VWS, LAND INTERACTION, AND A MORE VIGOROUS COLD/DRY NORTHERLY SURGE IN THE SOUTH CHINA SEA WILL RESULT IN A RAPID DECAY LEADING TO DISSIPATION BY TAU 72. THE NUMERICAL MODELS ARE IN BETTER AGREEMENT WITH MINIMAL SPREADING, LEADING TO FAIR CONFIDENCE IN THE JTWC TRACK FORECAST.// NNNN NNNN