WDPN31 PGTW 261500 MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION (TD) 27W/ WARNING NR 10// RMKS/ 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 261200Z1 TO 291200Z4 DEC 2003. A. TROPICAL DEPRESSION (TD) 27W, LOCATED APPROXIMATELY 410 NM EAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-SOUTHWESTWARD AT 03 KNOTS OVER THE PAST SIX HOURS. THE WARNING POSITION IS BASED ON 261130Z3 INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON CURRENT SATELLITE INTENSITY ESTIMATES OF 30 AND 35 KNOTS. A RECENT 261118Z9 SSMI REVEALS THAT THE LOW LEVEL CIRCULATION CENTER (LLCC) HAS BECOME FULLY EXPOSED WITH LITTLE CONVECTION OCCURRING OVER THE LLCC. B. TD 27W IS EXPECTED TO CONTINUE TO MOVE WEST-SOUTHWESTWARD UNDER THE STEERING INFLUENCE OF THE NORTHEAST MONSOON. ALL THE AVAILABLE DYNAMIC AIDS INCLUDING NOGAPS (NGPS), UK-MET OFFICE MODEL (EGRR), THE NCEP GFS (JAVN), GFDN, AND COAMPS, ARE IN GOOD AGREEMENT WITH THIS SCENARIO. THIS FORECAST IS BASED ON A BLEND OF PERSISTENCE AND ALL THE AVAILABLE DYNAMIC AIDS. C. TD 27W IS EXPECTED TO SLOWLY WEAKEN AS IT TRACKS SOUTHWESTWARD INTO A MORE UNFAVORABLE ENVIRONMENT OF INCREASING VERTICAL SHEAR AND CONVERGENT FLOW ALOFT. INTERACTION WITH THE NORTHEAST MONSOON, WITH DRY, COOL AIR IS EXPECTED TO FURTHER WEAKEN TD 27W AND AIDE IN THE DISSIPATION OF THE SYSTEM IN 36 TO 48 HOURS. D. FORECAST WIND RADII FORECAST ARE BASED ON CLIMATOLOGY FOR AN AVERAGE SIZED SYSTEM. 3. FORECAST TEAM: GRUBER/KLINZMMAN/TINOCO// NNNN