WDPN31 PGTW 040300 MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 19W WARNING NR 11// RMKS/ 1. FOR METEOROLOGISTS. 2. PROGNOSTIC REASONING FOR 040000Z TO 090000Z OCT 2006. A. TROPICAL STORM (TS) 19W (BEBINCA), LOCATED APPROXIMATELY 495 NM SOUTH-SOUTHEAST OF NAHA, OKINAWA HAS TRACKED NORTHWARD AT 07 KNOTS OVER THE PAST SIX HOURS. B. TS 19W HAS BEGUN TO TRACK NORTHWARD ALONG THE WESTERN FLANK OF A BUILDING PERIPHERAL ANTICYCLONE TO THE SOUTHEAST OF THE SYSTEM. CONFIDENCE IN THE NEAR TERM FORECAST IS INCREASING AS RECENT MULTI- SPECTRAL SATELLITE IMAGERY DEPICTS DEEP CONVECTION DEVELOPING OVER A NOW CONSOLIDATING LOW LEVEL CIRCULATION CENTER. AS THE DISTURBANCE TO THE NORTHEAST OF TS 19W LIFTS POLEWARD OVER THE NEXT 12 TO 24 HOURS, A PSEUDO REVERSE MONSOON TROUGH WILL FORM CAUSING THE SYSTEM TO BRIEFLY ACCELERATE TO THE NORTHEAST. AS THE AFOREMENTIONED DISTURBANCE BECOMES ABSORBED INTO THE MIDLATITUDE WESTERLIES NEAR TAU 72 HOWEVER, RIDGING WILL BUILD IN NORTH OF TS 19W CAUSING THE SYSTEM TO SLOW. THE AVAILABLE DYNAMIC AIDS ARE IN FAIR AGREEMENT WITH THIS SCENARIO AND THIS FORECAST IS BASED ON A CONSENSUS OF THE AVAILABLE DYNAMIC AIDS. C. RECENT ANIMATED MULTISPECTRAL SATELLITE IMAGERY INDICATES THE LOW LEVEL CIRCULATION CENTER (LLCC) IS BEGINNING TO BECOME BETTER ORGANIZED AND AN AREA OF DEEP CONVECTION IS FIRING ON THE WESTERN PERIPHERY OF THE LLCC. THE AREA OF CONVECTION ON THE NORTHERN PERIPHERY, WHILE IMPRESSIVE, NEVER WRAPPED INTO THE LLCC AND HAS NOT BEEN INCLUDED IN CURRENT INTENSITY ESTIMATES. DECREASING VERTICAL WIND SHEAR AND FAVORABLE DIFFLUENCE IN THE VICINITY OF THIS CONSOLI- DATING LLCC WILL ENABLE THE STORM TO INTENSIFICATION AT A CLIMATOLO- GICAL RATE. D. CURRENT WIND RADII ARE BASED ON SYNOPTIC OBSERVATIONS AND FORECAST WIND RADII ARE BASED ON CLIMATOLOGY FOR AN AVERAGE-SIZED SYSTEM. E. CONFIDENCE IN THE EXTENDED FORECAST IS ALSO INCREASING AS WE ARE ABLE TO BETTER ASCERTAIN THE CURRENT POSITION AND NEAR TERM FORECAST. IN THE EXTENDED TAUS, A SHORTWAVE RIDGE IS EXPECTED TO BUILD IN OVER THE SEA OF JAPAN AND HONSHU. THIS WILL CREATE AN ENVIRONMENT OF COMPETING STEERING INFLUENCES WITH A NORTHERLY STEERING INFLUENCE IMPARTED BY THE SHORTWAVE RIDGE TO THE NORTH COMBINES WITH THE SOUTHERLY STEERING INFLUENCE OF THE RIDGE TO THE EAST. THE NET RESULT WILL CAUSE TS 19W TO BECOME QUASI- STATIONARY. INTENSIFICATION AT A CLIMATOLOGICAL RATE WILL CONTINUE IN A FAVORABLE ENVIRONMENT. THE DEVELOPMENT OF A SIGNIFICANT POLEWARD OUTFLOW CHANNEL ASSOCIATED WITH THE MIDLATITUDE WESTERLIES COULD CAUSE INTENSIFICATION AT A GREATER THAN CLIMATOLOGICAL RATE TO OCCUR IN THE EXTENDED TAUS. FORECAST TEAM: BRAVO// NNNN