MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 06W (NOUL) WARNING NR 17// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 06W (NOUL), LOCATED APPROXIMATELY 809 NM EAST-SOUTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THE SPIRAL BANDING HAS DEEPENED AND WRAPPED TIGHTER INTO THE LOW LEVEL CIRCULATION CENTER. THE INITIAL POSITION IS BASED ON THE MSI LOOP AND EXTRAPOLATED FROM A MICROWAVE EYE FEATURE ON THE 062313Z F18 MICROWAVE PARTIAL PASS WITH FAIR CONFIDENCE. THE INITIAL INTENSITY IS BASED ON AN OVERALL ASSESSMENT OF DVORAK INTENSITY ESTIMATES FROM ALL REPORTING AGENCIES. UPPER LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH NEAR RADIAL OUTFLOW AND LOW TO MODERATE (10-15 KNOT) VERTICAL WIND SHEAR (VWS) THAT IS IN-PHASE WITH THE CURRENT STORM MOTION. TY NOUL IS TRACKING ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED SUB-TROPICAL RIDGE (STR) TO THE NORTHWEST. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY 06W WILL CONTINUE TO TRACK WEST-NORTHWESTWARD AS THE STR REMAINS THE DOMINANT STEERING MECHANISM. UPPER-LEVEL CONDITIONS, IN ADDITION TO PERENNIALLY WARM SSTS IN THE PHILIPPINE SEA WILL ENHANCE FURTHER INTENSIFICATION, PEAKING AT 115 KNOTS BY TAU 72. C. SHORTLY AFTER TAU 72, TY NOUL WILL BEGIN TO TURN POLEWARD AND START TO WEAKEN AS IT MAKES LANDFALL OVER NORTHERN LUZON NEAR CASIGURAN. IT WILL RAPIDLY ERODE AS IT DRAGS ACROSS RUGGED MOUNTAIN RANGES; HOWEVER, IT WILL STILL BE A STRONG TROPICAL STORM WHEN IT EXITS INTO THE SOUTH CHINA SEA NEAR LAOAG BY TAU 96. THE DYNAMIC MODEL GUIDANCE IS IN OVERALL GOOD AGREEMENT WITH GFDN AND COTC AS UNLIKELY OUTLIERS ON THE LEFT OF THE MODEL ENVELOPE. THE JTWC TRACK FORECAST IS LAID WITH LOW CONFIDENCE TOWARDS THE EXTENDED TAUS DUE TO THE LARGE SPREAD AMONG THE CONSENSUS MEMBERS.// NNNN NNNN