MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 27W (KALMAEGI) WARNING NR 027// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 27W (KALMAEGI), LOCATED APPROXIMATELY 302 NM NORTH- NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED NORTH-NORTHEASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. THERE IS GOOD CONFIDENCE IN THE INITIAL POSITION BASED ON AN OBLONG 15 NM PARTIAL EYE IN ENHANCED INFRARED SATELLITE IMAGERY AND A MICROWAVE EYE FEATURE IN A 190520Z SSMI 85 GHZ IMAGE WITH CONVECTION PRIMARLY OFFSET TO THE NORTH. THE INITIAL INTENSITY OF 75 KNOTS IS BASED ON MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T4.5-5.0 (77-90 KNOTS) AND A 190520Z SATCON ESTIMATE OF 72 KNOTS. STRONG POLEWARD OUTFLOW AND WARM (27-28 CELSIUS) SEA SURFACE TEMPERATURE (SST) ARE OFFSETTING STRONG (20-25 KT) VERTICAL WIND SHEAR (VWS) TO MAKE THE ENVIRONMENT MARGINALLY SUPPORTIVE. TY 27W IS DRIFTING LOOSELY BETWEEN A SUBTROPICAL RIDGE (STR) TO THE EAST AND ANOTHER CENTERED OVER THE SOUTH CHINA SEA TO THE WEST. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY 27W IS EXPECTED TO TURN SOUTHWESTWARD AND ACCELERATE AS THE STR TO THE WEST BECOMES THE DOMINANT STEERING MECHANISM. AROUND TAU 12, THE INTENSITY SHOULD WEAKEN RAPIDLY DUE TO STRONG VERTICAL WIND SHEAR (25-35 KTS) AND LAND INTERACTION AS IT CROSSES OVER LUZON. DISSIPATION IS EXPECTED BY TAU 72. WITH THE EXCEPTION OF THE UKMET ENSEMBLE MEAN, STRONG CROSS TRACK AGREEMENT AND FAIR ALONG-TRACK AGREEMENT IN NUMERICAL MODEL GUIDANCE PROVIDES MODERATE CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN NNNN