WDPN32 PGTW 300300 MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 22W (SINLAKU) WARNING/ NR 06// RMKS/ 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 300000Z3 AUG 02 TO 020000Z2 SEP 02. A. TROPICAL STORM (TS) 22W, LOCATED APPROXIMATELY 750 NM EAST- SOUTHEAST OF IWO JIMA, HAS TRACKED NORTH-NORTHWESTWARD AT 09 KNOTS DURING THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON 292330Z9 MULTISPECTRAL SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE CURRENT INTENSITY ESTIMATES OF 55 KNOTS. A 292010Z4 SPECIAL SENSOR MICROWAVE IMAGER (SSM/I) PASS REVEALS TIGHTLY CURVED BANDING FEATURES. B. A TUTT TO THE NORTHEAST OF TS 22W APPEARS TO HAVE PENETRATED THE MID-LEVEL SUBTROPICAL RIDGE, CREATING A TEMPORARY WEAKNESS. DURING THE NEXT 12 TO 24 HOURS, THE TUTT IS EXPECTED TO SLOWLY FILL AND DRIFT NORTHEASTWARD ALLOWING THE RIDGE TO BUILD BACK IN. TS 22W IS FORECAST TO TRACK NORTHWESTWARD IN THE EARLY PERIOD, THEN TRACK WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE TO THE NORTH FOR THE REMAINDER OF THE FORECAST PERIOD. THE AVAILABLE DYNAMICAL MODELS INCLUDING NOGAPS, UKMET (EGRR), JAPANESE TYPHOON (JTYM), AND GFDN MODELS ARE IN GOOD AGREEMENT WITH THIS SCENARIO. NCEP AVIATION (AVN) MODEL INITIALIZES THE SYSTEM WEAKER THAN THE OTHER DYNAMIC AIDS AND TRACKS THE SYSTEM MORE SLOWLY. OUR FORECAST IS BASED ON PERSISTENCE AND A BLEND OF ALL AVAILABLE DYNAMIC AIDS WITH LESS EMPHASIS ON THE AVN SOLUTION. C. THE SYSTEM IS FORECAST TO INTENSIFY THROUGHOUT THE FORECAST PERIOD WITH SOME IMPROVED OUTFLOW PROVIDED BY AN UPPER LEVEL TROUGH SITUATED TO THE WEST. D. THE WIND RADII ANALYSIS IS BASED ON MICROWAVE DATA AND A RECENT QUIKSCAT PASS. FORECAST WIND RADII ARE BASED ON CLIMATOLOGY FOR AN AVERAGE-SIZED SYSTEM. FORECAST TEAM: BRYANT/JACOBS/SHERRY/NUTONGLA// NNNN