WDPN34 PGTW 030300 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 030000Z3 TO 060000Z6 SEP 02. A. TYPHOON (TY) 02C (ELE), LOCATED APPROXIMATELY 425 NM WEST- SOUTHWEST OF MIDWAY ISLAND, HAS TRACKED NORTH-NORTHEASTWARD AT 09 KNOTS OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON 022330Z0 MULTI-SPECTRAL SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE CURRENT INTENSITY ESTIMATES OF 115 KNOTS. ANIMATED WATER VAPOR IMAGERY INDICATES THAT POLEWARD OUTFLOW CONTINUES TO BE FAVORABLE. B. A PASSING SHORTWAVE TROUGH HAS CAUSED A BREAK IN THE MID-LEVEL RIDGE SITUATED TO THE NORTH-NORTHEAST OF TY 02C. THE CYCLONE IS FORECAST TO TRACK NORTH-NORTHEASTWARD TOWARDS THIS WEAKNESS BEFORE THE TROUGH FILLS EARLY IN THE PERIOD. THEREAFTER, THE MID-LEVEL RIDGE IS EXPECTED TO BUILD BACK IN TOWARDS THE NORTHEAST RESULTING IN A NORTHWESTWARD TURN. OUR FORECAST IS BASED ON A BLEND OF ALL AVAILABLE DYNAMIC MODELS (UKMET GLOBAL, NOGAPS, GFDN, AVN, JMA GLOBAL SPECTRAL AND TYPHOON MODELS). C. TY 02C IS EXPECTED TO MAINTAIN ITS INTENSITY THROUGH THE FIRST 48 HOURS AS UPPER LEVEL CONDITIONS REMAIN FAVORABLE. THEREAFTER, THE SYSTEM IS FORECAST TO BEGIN WEAKENING AS IT ENCOUNTERS INCREASED VERTICAL WIND SHEAR AND COOLER SEA SURFACE TEMPERATURES. D. INITIAL WIND RADII ANALYSIS IS BASED ON A RECENT QUIKSCAT PASS. FORECAST WIND RADII ARE BASED ON CLIMATOLOGY FOR AN AVERAGE- SIZED SYSTEM. 3. FORECAST TEAM: VILPORS/KENDALL/DANIEL/RONSSE/SCHAEFER/EDBERG/ COOK// NNNN