MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 21W (DUJUAN) WARNING NR 29// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 21W (DUJUAN), LOCATED APPROXIMATELY 90 NM WEST- SOUTHWEST OF TAIPEI, TAIWAN, HAS TRACKED WESTWARD AT 13 KNOTS OVER THE PAST SIX HOURS. TY 21W HAS RE-EMERGED OVER WATER AND, AS DEPICTED IN ANIMATED ENHANCED INFRARED SATELLITE IMAGERY, HAS WEAKENED CONSIDERABLY WITH CONVECTIVE BANDING WRAPPING TIGHTLY INTO THE CENTER. RADAR IMAGERY FROM TAIWAN AND A 281737Z GCOM 37 GHZ IMAGE REVEAL TIGHTLY-CURVED DEEP CONVECTIVE BANDING WRAPPING INTO AN ELONGATED CENTER. OVERALL, BASED ON RADAR FIXES AND IMAGERY, THERE IS GOOD CONFIDENCE IN THE INITIAL POSITION. TY 21W REMAINS A STRONG SYSTEM AND IS ASSESSED AT 90 KNOTS BASED ON THE PGTW DVORAK INTENSITY ESTIMATE OF 90 KNOTS. UPPER-LEVEL ANALYSIS INDICATES THE SYSTEM REMAINS IN A LOW (5-10 KNOTS) VERTICAL WIND SHEAR AREA WITH GOOD RADIAL OUTFLOW. THE SYSTEM IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE. 3. FORECAST REASONING. A. NO SIGNIFICANT CHANGE IN THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY DUJUAN WILL MAINTAIN A WEST-NORTHWESTWARD TRAJECTORY UP TO TAU 18 BEFORE DEFLECTING NORTHWARD IN RESPONSE TO AN APPROACHING MIDLATITUDE TROUGH OVER CHINA. DUE TO LAND INTERACTION AND COOLING SEA SURFACE TEMPERATURES IN THE TAIWAN STRAIT, THE SYSTEM WILL CONTINUE TO WEAKEN RAPIDLY. WITHIN THE NEXT 12 HOURS, TY 21W WILL MAKE LANDFALL ALONG THE COAST OF CHINA AND IS FORECAST TO RAPIDLY WEAKEN AS IT TRACKS POLEWARD. TY 21W SHOULD DISSIPATE BY TAU 36, HOWEVER, THE REMNANTS MAY TRACK OVER THE EAST CHINA SEA. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT THROUGHOUT THE FORECAST PERIOD LENDING HIGH CONFIDENCE TO THE JTWC FORECAST WHICH IS IN LINE WITH MULTI-MODEL CONSENSUS.// NNNN NNNN