WDPN31 PGTW 171500 MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION (TD) 12W/ WARNING NR 10// RMKS/ 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 171200Z1 TO 201200Z5 AUG 2003. A. TROPICAL DEPRESSION (TD) 12W, LOCATED APPROXIMATELY 140 NM WEST-NORTHWEST OF GUAM, HAS TRACKED WEST-NORTHWESTWARD AT 13 KNOTS OVER THE PAST 06 HOURS. THE WARNING POSITION IS BASED ON 171130Z3 ENHANCED INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE CURRENT INTENSITY ESTIMATES OF 25 KNOTS. A 170833Z2 QUIKSCAT PASS DEPICTS CONVERGENT FLOW NEAR THE DEEP CONVECTION, BUT NO LOW LEVEL CIRCULATION CENTER. ANIMATED SATELLITE IMAGERY SUGGESTS THE DEEP CONVECTION IS ASSOCIATED WITH A MID-LEVEL CIRCULATION. B. TD 12W IS FORECAST TO TRACK NORTHWESTWARD UNDER THE SOUTHWEST QUADRANT OF THE LOW TO THE MID-LEVEL STEERING RIDGE TO THE NORTH. AVAILABLE DYNAMIC AIDS, CONSISTING OF NOGAPS, NCEP (GFS), EGRR, AFWA MM5, JGSM, AND COAMPS ARE IN GOOD AGREEMENT, WITH THE EXCEPTION OF MM5. AFWA MM5 IS SIGNIFICANTLY FASTER THAN THE OTHER DYNAMIC AIDS. THIS FORECAST IS BASED ON A BLEND OF PERSISTENCE AND A CONSENSUS OF THE AVAILABLE DYNAMIC AIDS WITH LESS EMPHASIS ON MM5. C. INTENSIFICATION OF TD 12W CONTINUES TO BE DELAYED DUE TO SLIGHT UPPER LEVEL CONVERGENCE ON THE WESTWARD QUADRANT OF THE SYSTEM. ANIMATED WATER VAPOR IMAGERY INDICATES THAT AN UPPER LEVEL LOW NORTHWEST OF THE SYSTEM IS INHIBITING VENTILATION. BASED ON NO EVIDENCE OF A LOW LEVEL CIRCULATION CENTER AND A MARGINAL UPPER LEVEL ENVIRONMENT, TD 12W IS EXPECTED MAINTAIN INTENSITY THROUGH 24 TO 48 HOURS AND THEN DISSIPATE BY 72 HOURS. D. THIS SYSTEM DOES NOT REQUIRE WIND RADII. FORECAST TEAM: WINGEART/DAMRON/ALLEN/LAM/ANDERSON// NNNN