WDPN31 PGTW 030300 MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 14W WARNING NR 20// RMKS/ 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 030000Z TO 080000Z SEP 2005. A. SUPER TYPHOON (STY) 14W (NABI), LOCATED APPROXIMATELY 475 NM SOUTHEAST OF OKINAWA, HAS TRACKED NORTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. B. THERE HAVE BEEN NO SIGNIFICANT CHANGES IN THE PRIMARY SYNOPTIC STEERING INFLUENCE OF STY 14W OVER THE LAST 12 HOURS. THE SYSTEM CONTINUES TO TRACK ALONG THE SOUTHWESTERN PERIPHERY OF THE MIDLEVEL STEERING RIDGE CENTERED SOUTHEAST OF JAPAN. A STRONG PERIPHERAL ANTI- CYCLONE, EVIDENT IN UPPER AIR ANALYSES, HAS BEEN CONSIDERED AS ADDING AN ADDITIONAL POLEWARD COMPONENT TO THE FORECAST TRACK. A MIDLATITUDE TROUGH PROPAGATING EASTWARD ACROSS ASIA IS FORECAST TO WEAKEN THE STEERING RIDGE BETWEEN TAUS 48 AND 72, ALLOWING STY 14W TO TRACK EVEN MORE POLEWARD BEYOND TAU 48. THE AVAILABLE DYNAMIC AIDS CONSISTING OF NOGAPS, GFDN, COAMPS, AFWA MM5, NCEP GFS, UKMET EGRR, JGSM, JTYM, TCLAPS AND WBAR ARE IN FAIR AGREEMENT WITH THIS SCENARIO THROUGH TAU 48. THERE ARE MORE DRAMATIC DIFFERENCES IN THE MODEL DEPICTIONS OF THE STEERING RIDGE BEYOND TAU 48, AND FORECAST CONFIDENCE WANES BEYOND THIS TIME. THIS FORECAST IS BASED ON A CONSENSUS OF ALL AVAILABLE DYNAMIC AIDS, WITH LESS EMPHASIS ON MM5, A POLEWARD OUTLIER. C. RECENT MULTISPECTRAL AND MICROWAVE SATELLITE IMARGEY INDICATES A LARGE WELL DEFINED EYE, APPROXIMATELY 50NM WIDE. UPPER AIR ANALYSIS AND ANIMATED WATER VAPOR IMAGERY DEPICTS A FILLING UPPER LEVEL LOW LOCATED TO THE WEST OF STY 14W WHICH IF LINKAGE SHOULD OCCUR, WOULD PROVIDE ADDITIONAL OUTFLOW. MODEST RE-INTENSIFICATION IS FORECAST AS OUTFLOW IMPROVES AND THE STORM REMAINS IN A LOW TO MODERATE VERTICAL WIND SHEAR ENVIRONMENT THROUGH TAU 72. D. CURRENT WIND RADII ARE BASED ON A 022103Z QUIKSCAT AND A 22145Z SSM/I PASS. FORECAST WIND RADII ARE BASED ON CLIMATOLOGY FOR A LARGE SIZED SYSTEM. E. IN THE EXTENDED PERIOD, STY 14W IS FORECAST TO TRACK POLEWARD THROUGH THE WEAKNESS IN THE STEERING RIDGE. STY 14W IS FORECAST TO SLOW AS IT APPROACHES THE RIDGE AXIS AND BEGINS TO RECURVE NORTHEAST- WARD. ONCE STY 14W RECURVES IT WILL BEGIN TO INTERACT WITH THE MID- LATITUDE WESTERLIES AND TRAVERSE LOWER SEA-SURFACE TEMPERATURES LEADING AN INITIAL WEAKENING TREND BY TAU 96. BY THE END OF THE FORECAST PERIOD, THE SYSTEM WILL INTERACT WITH LAND AND RAPIDLY TRACK INTO THE SEA OF JAPAN AS IT UNDERGOES THE EARLY STAGES OF EXTRA- TROPICAL TRANSITION. 3. FORECAST TEAM: DELTA//