WDPN31 PGTW 310300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 06W (SIX) WARNING NR 07// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 06W (NIDA), LOCATED APPROXIMATELY 200 NM NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED NORTHWESTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP FLARING CENTRAL CONVECTION FORMING A COLD DENSE OVERCAST OBSCURING THE LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON A 302241Z SSMIS 91 GHZ IMAGE SHOWING A STRONG BAND OF CONVECTION ON THE WESTERN PERIPHERY WRAPPING TIGHTLY INTO THE LLCC. CONVECTIVE ACTIVITY AND WIND SPEEDS ARE CURRENTLY BEING INFLUENCED BY INTERACTION WITH THE TOPOGRAPHIC FEATURES OF EASTERN LUZON. THE INTENSITY IS ASSESSED AT 55 KNOTS AND IS BASED ON OBJECTIVE DVORAK ESTIMATES FROM ALL AGENCIES REPORTING T3.5 (55 KNOTS). THE STEERING MECHANISM FOR TS 06W IS CURRENTLY TRANSITIONING TO A SUBTROPICAL RIDGE TO THE NORTH, AND THIS TRANSITION IS RESPONSIBLE FOR THE DECREASE IN TRACK SPEED OVER THE LAST 12 HOURS. RECENT DATA SHOWS THE SYSTEM HAS BEGUN ACCELERATING, SUGGESTING THE RIDGE IS BEGINNING TO TAKE HOLD. THE ENVIRONMENT IS FAVORABLE WITH WIND SHEAR VALUES NEAR 5 TO 10 KNOTS, SSTS IN EXCESS OF 30 CELSIUS WITH SUBSTANTIAL OCEANIC HEAT CONTENT, AND A NEAR ANTICYCLONE FORMING OVER THE SYSTEM. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 06W WILL CONTINUE TO ACCELERATE WEST-NORTHWESTWARD IN THE NEXT 12 HOURS AS THE STEERING RIDGE TO THE NORTH REORIENTS. INTENSITY IS EXPECTED TO INCREASE DUE TO THE FAVORABLE ENVIRONMENT, BUT INTENSIFICATION WILL BE LIMITED AS THE SYSTEM SKIRTS THE COASTLINE OF NORTHERN LUZON THROUGH TAU 18. THE SYSTEM IS EXPECTED TO MAINTAIN ITS STRUCTURE FAIRLY WELL AS IT RESURFACES OVER WATER IN THE SOUTH CHINA SEA WITH FURTHER INTENSIFICATION EXPECTED. TS 06W WILL CONTINUE ITS WEST-NORTHWESTWARD TRACK UNTIL IT MAKES LANDFALL NEAR HONG KONG AROUND TAU 48. C. IN THE EXTENDED TAUS, TS 06W SHOULD WEAKEN RAPIDLY AS IT TRACKS WESTWARD INTO CHINA, DISSIPATING BY TAU 96. DYNAMIC MODEL GUIDANCE IS IN VERY TIGHT AGREEMENT AND HAS BEEN OVER THE LAST 24 HOURS SHOWING THE DEEP LAYERED RIDGE ANCHORED OVER CHINA INFLUENCING A WEST-NORTHWESTWARD TRACK. THE FORECAST TRACK IS PLACED NEAR THE MULTI-MODEL CONSENSUS TRACK, AND DUE TO THE TIGHT AGREEMENT OF MODEL SOLUTIONS, THERE IS HIGH CONFIDENCE IN THE FORECAST TRACK./=