WDPN31 PGTW 151500 MSGID/GENADMIN/NAVPACMETOCCEN PEARL//JTWC// SUBJ/PROGNOSTIC REASONING FOR TYPHOON (TY) 12W (FENGSHEN) WARNING NR 06// RMKS/ 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 151200Z9 TO 181200Z2 JUL 02. A. TYPHOON (TY) 12W (FENGSHEN), LOCATED APPROXIMATELY 400 NM SOUTHEAST OF WAKE ISLAND, HAS TRACKED NORTHWARD AT 03 KNOTS OVER THE PAST SIX HOURS. THE WARNING POSITION IS BASED ON 151130Z1 ENHANCED INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE CURRENT INTENSITY ESTIMATES OF 90 KNOTS. ENHANCED INFRARED IMAGERY DEPICTS 6NM RAGGED EYE. A 150946Z5 SPECIAL SENSOR MICROWAVE IMAGER (SSM/I) PASS REVEALS A COMPACT SYSTEM WITH THE DEEP CONVECTION REMAINING DIRECTLY CENTERED OVER THE LOW LEVEL CIRCULATION CENTER (LLCC) AND ONLY WEAK RAINBANDS. B. TY 12W IS EXPECTED TO TRACK NORTHWARD IN THE EARLY PERIOD AND THEN ALONG THE PERIPHERY OF A STEERING RIDGE LOCATED NORTH-NORTHEAST OF THE SYSTEM. AFTER THE EARLY PERIOD, THE RIDGE BUILDS, STEERING TY 12 ON A MORE WESTWARD TRACK. AVAILABLE DYNAMIC AIDS, CONSISTING OF NCEP AVIATION (AVN), NOGAPS, AND THE JAPANESE GLOBAL (JGSM) AND TYPHOON (JTYM) MODELS ARE IN GOOD AGREEMENT WITH THIS SCENARIO. OUR FORECAST IS A BLEND OF ALL AVAILABLE DYNAMIC AIDS WITH CONSIDERATION FOR PERSISTENCE IN THE EARLY PERIOD. C. TY 12W IS FORECAST TO INTENSIFY MORE SLOWLY THROUGHOUT THE FORECAST PERIOD THAN ITS PREVIOUS RAPID DEVELOPMENT. POLEWARD OUTFLOW PREVIOUSLY ENHANCED BY AN UPPER LEVEL LOW TO THE NORTHEAST IS NOW NO LONGER OCCURRING. A LESS FAVORABLE ENVIRONMENT FOR OUTFLOW DEVELOPMENT OVER THE FORECAST PERIOD WILL HINDER MUCH FURTHER DEVELOPMENT OF THE SYSTEM. D. FORECAST WIND RADII ARE BASED ON CLIMATOLOGY FOR A MIDGET SIZED SYSTEM. 3. FORECAST TEAM: BRYANT/JACOBS/SHERRY/NUTONGLA// NNNN