WDXS31 PGTW 220900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 01S (PADDY) WARNING NR 001// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 13.3S 108.2E INITIAL INTENSITY: 35 KTS GEOGRAPHIC REFERENCE: 225 NM SOUTHEAST OF CHRISTMAS ISLAND, AUSTRALIA MOVEMENT PAST 6 HOURS: SOUTHWARD AT 06 KTS SIGNIFICANT WAVE HEIGHT: 12 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS AN AREA OF DEEP, FLARING CONVECTION WITH SLIGHTLY FRAGMENTED BANDING WRAPPING INTO AN ASSESSED LOW LEVEL CIRCULATION CENTER (LLCC). A 220153Z ASCAT-B PASS INDICATES 35 KNOT WINDS SURROUNDING THE LLCC WITHIN 50 NM. TC PADDY IS IN A FAVORABLE ENVIRONMENT WITH GOOD POLEWARD OUTFLOW ALOFT, LOW (10-15 KTS) VERTICAL WIND SHEAR (VWS), AND WARM (28-29 C) SEA SURFACE TEMPERATURES (SST). THE INITIAL POSITION AND INTENSITY ARE BOTH PLACED WITH HIGH CONFIDENCE BASED OFF THE AFOREMENTIONED MSI AND ASCAT DATA. INITIAL WIND RADII BASIS: SCATTEROMETER DATA CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) LOCATED TO THE SOUTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T1.5 - 25 KTS FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 10-15 KTS SST: 28-29 CELSIUS OUTFLOW: MODERATE POLEWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: HIGH INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THIS INITIAL PROGNOSTIC REASONING MESSAGE ESTABLISHES THE FORECAST PHILOSOPHY. FORECAST DISCUSSION: TC PADDY WAS HEADING IN A PREDOMINATELY SOUTHEASTWARD DIRECTION PRIOR TO DEVELOPMENT. HOWEVER, OVER THE PAST 6 HOURS IT HAS TRACKED SOUTHWARD DUE TO THE STR SLOWLY BUILDING IN FROM THE SOUTHEAST. AS THE STR CONTINUES TO BUILD, TC PADDY WILL TURN SOUTHWESTWARD BY TAU 12. BY TAU 24, TC PADDY WILL MAKE ITS FINAL TURN WESTWARD AND WILL RIDE ANOTHER, MORE BROADER STR BUILDING IN FROM THE SOUTH. BY TAU 36, TC PADDY WILL CONTINUE THIS WESTWARD TRACK AND WILL BEGIN TO ENCOUNTER AN AREA OF INCREASED VWS AND CONSISTENT DRIER AIR BEING INTRODUCED FROM THE SOUTHWEST. CONDITIONS WILL CONTINUE TO BECOME MORE UNFAVORABLE THROUGHOUT THE REMAINDER OF THE FORECAST TRACK. FULL DISSIPATION IS EXPECTED BY TAU 72. MODEL DISCUSSION: AVAILABLE MODEL GUIDANCE INDICATES THAT TC PADDY WILL MAKE THE SOUTHWESTWARD TURN, FOLLOWED BY A MORE STRAIGHT FORWARD WESTWARD TRACK AFTER TAU 24. THE JTWC TRACK IS PLACED WITH MEDIUM CONFIDENCE, HEDGED CLOSELY TO THE ECMWF FORECAST TRACKS. THE JTWC FORECAST INTENSITY IS SET WITH MEDIUM CONFIDENCE AND IN AGREEMENT WITH AVAILABLE MODEL GUIDANCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM// NNNN