WDPN31 PGTW 080300 MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TYPHOON (TY) 03W (SUDAL) WARNING /NR 17// RMKS/ 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 080000Z8 TO 130000Z4 APR 2004. A. TYPHOON (TY) 03W (SUDAL), LOCATED APPROXIMATELY 125 NM EAST OF YAP, HAS TRACKED WEST-SOUTHWESTWARD AT 09 KNOTS OVER THE PAST 06 HOURS. THE WARNING POSITION IS BASED ON 072330Z5 MULTI-SPECTRAL SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE CURRENT INTENSITY ESTIMATES OF 100 AND 115 KNOTS. A RECENT VISIBLE SATELLITE IMAGERY AND A 072130Z3 MICROWAVE PASS BOTH SHOW A DISTINCT EYE. B. THE STEERING ENVIRONMENT OF TY 03W HAS BEEN DOMINATED BY A BUILDING RIDGE FROM THE NORTHWEST WHICH HAS CAUSED TY 03W TO TRACK MORE EQUATORWARD. THE NCEP GFS MODEL HAS MANAGED THE FORECASTED STEERING ENVIRONMENT WITH THE GREATEST SKILL. A TRANSIENT MID LATITUDE SHORTWAVE TROUGH WILL WEAKEN THE DOMINANT STEERING RIDGE, WHICH WILL TRANSITION TY 03W TO A MORE POLEWARD STEERING ENVIRONMENT. A PERIPHERAL RIDGE WILL BUILD TO THE EAST SENDING TY 03W STRAIGHT POLEWARD AND MOVE TY 03W UNDER THE SUBTROPICAL RIDGE AXIS. THE AVAILABLE DYNAMIC AIDS, CONSISTING OF NOGAPS, EGRR, GFDN, NCEP GFS, COAMPS, AFWA, TLAPS, TCLAPS, JGSM, JTYM AND WBAR ARE IN GOOD AGREEMENT WITH THIS SCENARIO THOUGH NCEP GFS HANDLES THE INITIAL MOVEMENT OF TY 03W BETTER THAN THE OTHERS. THIS FORECAST IS BASED ON A CONSENSUS OF ALL AVAILABLE DYNAMIC AIDS WITH MORE EMPHASIS ON THE NCEP GFS SOLUTION EARLY IN THE FORECAST PERIOD. C. TY 03W IS FORECAST TO INTENSIFY AT A NEAR CLIMATOLOGICAL RATE THROUGH THE FORECAST PERIOD IN AN ENVIRONMENT OF MODERATE POLEWARD OUTFLOW AND FAVORABLE VERTICAL SHEAR AS THE SYSTEM APPROACHES THE UPPER LEVEL RIDGE AXIS. D. CURRENT WIND RADII AND FORECAST WIND RADII ARE BASED ON CLIMATOLOGY FOR AN AVERAGE SIZED SYSTEM. E. THE LONG RANGE FORECAST TRACK MAINTAINS TY 03W UNDER THE SUBTROPICAL RIDGE AXIS AND ATTAINS MAXIMUM INTENSITY OF SUPER TYPHOON STRENGTH, WHICH IS CORROBORATED BY CIMSS EXPERIMENTAL VERTICAL SHEAR TC INTENSITY TREND ESTIMATES. TY 03W WILL SLOWLY RECURVE TO THE NORTHEAST BY THE VERY END OF THE FORECAST PERIOD. RELEASED BY LCDR ARENDS, USN. FORECAST TEAM: ARENDS/JACOBS/HEILER/SCHULTZ/ NNNN