MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 27W (KALMAEGI) WARNING NR 29// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON 27W (KALMAEGI), LOCATED APPROXIMATELY 250 NM NORTH- NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED SOUTHWESTWARD AT 03 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY REVEALS A PARTIALLY EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC) JUST NORTH OF PALAUI ISLAND, PHILIPPINES WITH THE CONVECTION BEING SHEARED TO THE NORTH OF THE LLCC. THERE IS HIGH CONFIDENCE IN THE INITIAL POSITION BASED ON A 191304Z ASCAT-A PASS THAT SHOWS A COMPACTS LLCC. THE INITIAL INTENSITY OF 65 KNOTS IS BASED ON MULTI- AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T4.0 (65 KNOTS). DECENT POLEWARD OUTFLOW AND WARM (27-28 CELSIUS) SEA SURFACE TEMPERATURE (SST) ARE PARTIALLY OFFSETTING THE STRONG (25-30 KT) VERTICAL WIND SHEAR (VWS) IMPACTING TY 27W, MAKING THE ENVIRONMENT OVERALL MARGINAL. TY 27W HAS BEEN QUASI-STATIONARY OVER THE PAST 12 HOURS DRIFTING BETWEEN A SUBTROPICAL RIDGE (STR) TO THE EAST AND ANOTHER STR 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 WILL PROGRESS SOUTHWESTWARD ACROSS NORTHWESTERN LUZON AND ACCELERATE AS THE STR TO THE WEST BECOMES THE DOMINANT STEERING MECHANISM. THE SYSTEM IS EXPECTED TO RAPIDLY WEAKEN AS IT ENCOUNTERS THE RUGGED TERRAIN AND WILL DROP TO 45 KNOTS BY TAU 12. TY 27W WILL ENTER THE SOUTH CHINA SEA AROUND TAU 18 AND WILL THEN GRADUALLY WEAKEN WITH MINIMAL UPPER LEVEL OUTFLOW AND MODERATE VERTICAL WIND SHEAR, LEADING TO DISSIPATION BY TAU 72. THERE IS STRONG CROSS TRACK AGREEMENT AND FAIR ALONG-TRACK AGREEMENT IN NUMERICAL MODEL GUIDANCE, LENDING MODERATE CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN NNNN