WDPN31 PGTW 250300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 03W (SANVU) WARNING NR 16// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 03W (SANVU), LOCATED APPROXIMATELY 190 NM SOUTHWEST OF IWO TO, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) INDICATES THAT TY 03W HAS DEVELOPED A RAGGED, CLOUD FILLED EYE. A WELL DEVELOPED MICROWAVE EYE IS STILL EVIDENT IN A 37 GHZ 242013Z SSMIS PASS AND THE CONCURRENT 91 GHZ IMAGE REVEALS DEEP CONVECTIVE BANDING AROUND 75 PERCENT OF THE MICROWAVE EYE FEATURE. THERE IS HIGH CONFIDENCE IN THE INITIAL POSITION BASED ON THE RAGGED EYE IN MSI. THE INITIAL INTENSITY OF 80 KNOTS IS BASED ON AGREEABLE DVORAK FIXES FROM KNES AND PGTW AT 25/00Z. UPPER LEVEL ANALYSIS AROUND THE SYSTEM SHOWS LOW TO MODERATE WESTERLY VERTICAL WIND SHEAR (VWS) WITH STRONG DIFFLUENT FLOW ALOFT. ANIMATED WATER VAPOR IMAGERY INDICATES THAT THE SYSTEM IS EXPERIENCING ENHANCED POLEWARD OUTFLOW INTO THE MID-LATITUDE WESTERLIES AND SOMEWHAT INHIBITED OUTFLOW TO THE WEST/NORTHWEST AS TY 03W BEGINS TO FEEL THE EFFECTS OF THE APPROACHING UPPER LEVEL TROUGH. TY SANVU HAS STARTED TO RE-CURVE AND ACCELERATE ALONG THE NORTHWESTERN PERIPHERY OF THE SUBTROPICAL RIDGE, AND IS EXPECTED TO CONTINUE TRACKING NORTHEASTWARD AS IT INTERACTS WITH THE BAROCLINIC ZONE TO THE NORTH. 3. FORECAST REASONING. A. THE FORECAST PHILOSOPHY HAS NOT CHANGED SINCE THE PREVIOUS PROGNOSTIC REASONING BULLETIN. B. TY 03W MAY STILL INTENSIFY SLIGHTLY WITHIN THE NEXT 12 HOURS AS IT REMAINS IN A FAVORABLE UPPER LEVEL ENVIRONMENT AND CONTINUES TO TRACK OVER WARM SEA SURFACE TEMPERATURES (SST). AFTER TAU 12, THE SYSTEM SHOULD BEGIN TO GRADUALLY WEAKEN AS IT ENCOUNTERS INCREASED WESTERLY VERTICAL WIND SHEAR AND A STEEP DROP OFF IN SST. BETWEEN TAU 36 AND TAU 48, TY 03W WILL BEGIN TO INTERACT WITH THE BAROCLINIC ZONE, AND BY TAU 72 THE SYSTEM WILL BECOME COMPLETELY EMBEDDED IN THE MID-LATITUDE WESTERLY FLOW AS A GALE FORCE EXTRA-TROPICAL LOW. AVAILABLE NUMERICAL MODEL GUIDANCE REMAINS TIGHTLY PACKED AND NOGAPS ALONG-TRACK SPEEDS FOR THE LATER TAUS HAVE COME MORE IN LINE WITH OTHER CONSENSUS MEMBERS. THE OFFICIAL JTWC FORECAST TRACK IS CLOSE TO CONSENSUS AND CONSISTENT WITH THE PREVIOUS FORECAST TRACK. THERE IS HIGH CONFIDENCE IN THE FORECAST TRACK BASED ON THE PERSISTENCE OF THE JTWC TRACK AND MINIMAL SPREAD IN THE DYNAMIC AIDS AND ECMWF ENSEMBLE MEMBERS.// NNNN