WTXS32 PGTW 102100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 03S (THREE) WARNING NR 009// RMKS/ 1. TROPICAL CYCLONE 03S (THREE) WARNING NR 009 02 ACTIVE TROPICAL CYCLONES IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 101800Z --- NEAR 16.9S 114.4E MOVEMENT PAST SIX HOURS - 135 DEGREES AT 14 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT REPEAT POSIT: 16.9S 114.4E --- FORECASTS: 12 HRS, VALID AT: 110600Z --- 19.3S 117.1E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 130 DEG/ 20 KTS --- 24 HRS, VALID AT: 111800Z --- 21.8S 120.3E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND VECTOR TO 36 HR POSIT: 135 DEG/ 20 KTS --- 36 HRS, VALID AT: 120600Z --- 24.6S 123.4E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 102100Z POSITION NEAR 17.5S 115.1E. 10DEC20. TROPICAL CYCLONE 03S (THREE), LOCATED APPROXIMATELY (100*PI) NM NORTHWEST OF PORT HEDLAND, AUSTRA, HAS TRACKED SOUTHEASTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY REVEALS A THAT THE SYSTEM IS BEGINNING TO FEEL THE EFFECTS OF SHEAR AHEAD OF AN APPROACHING MID-LATITUDE TROUGH TO THE SOUTHWEST, WITH CONVECTION BEING SHEARED INTO AN ELONGATED PLUME TO THE SOUTHEAST OF THE LOW-LEVEL CIRCULATION CENTER (LLCC). IN THE ABSSENCE OF RECENT MICROWAVE IMAGERY, THE INITIAL POSITION IS PLACED WITH ONLY MODERATE CONFIDENCE, BASED PRIMARILY ON SPIRAL BAND ANALYSIS OF THE OUTER LOW-LEVEL CLOUD BANDS EVIDENT IN THE INFRARED IMAGERY. THE INITIAL INTENSITY IS ASSESSED AT 35 KNOTS WITH MODERATE CONFIDENCE AND IS AN AVERAGE VALUE OF THE PGTW DVORAK CURRENT INTENSITY ESTIMATE OF T2.0 (30 KNOTS), AN ADVANCED DVORAK TECHNIQUE (ADT) ESTIMATE OF T3.0 (45 KNOTS) AND A SATELLITE CONSENSUS ESTIMATE OF 46 KNOTS. ENVIRONMENTAL ANALYSIS INDICATES THAT THE SYSTEM IS MOVING THROUGH A MARGINAL ENVIRONMENT WITH LOW (10-15 KNOTS) VERTICAL WIND SHEAR, ROBUST POLEWARD OUTFLOW, AND WARM (29-30 DEG C) SSTS. THE SYSTEM WILL TRACK SOUTHEAST THROUGH THE DURATION OF THE FORECAST ALONG THE SOUTHWESTERN PERIPHERY OF A DEEP- LATER STR LOCATED OVER NORTHERN AUSTRALIA, AND IS FORECAST TO MAKE LANDFALL NEAR PORT HEDLAND IN APPROXIMATELY 12-15 HOURS. OVER THE NEXT 12 HOURS, THE SYSTEM IS FORECAST TO INTENSITY TO 40 KNOTS, AS IT BEGINS TO INTERACT WITH APPROACHING TROUGH, WHICH WILL PROVIDE FOR A SHORT PERIOD OF ENHANCED POLEWARD OUTFLOW INTO THE DIVERGENT FLOW AHEAD OF THE BASE OF THE TROUGH, PRIOR TO THE ONSET OF INCREASING VWS WHICH WILL SERVE TO DECAPITATE THE SYSTEM. AFTER LANDFALL, THE SYSTEM WILL DISSIPATE AS IT TRACKS OVER LAND, FULLY DISSIPATING AS A TROPICAL CYCLONE BY TAU 36. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT WITH AN 50NM SPREAD IN SOLUTIONS AT LANDFALL, INCREASING TO 90NM BY TAU 24. WHILE CROSS-TRACK SPREAD IS RELATIVELY LOW, ALONG-TRACK SPREAD HAS BEEN STEADILY INNCREASING RUN TO RUN, WITH AS MUCH AS 100NM SPREAD NOW AT TAU 12, AS THE MODELS VARY IN HOW THEY HANDLE THE DEGREE OF TROUGH INTERACTION. IN LIGHT OF THE INCREASING ALONG-TRACK SPREAD, THERE IS OVERALL FAIR CONFIDENCE IN THE JTWC FORECAST TRACK, WHICH LIES CLOSE TO AND SLIGHTLY SLOWER THAN THE MULTI-MODEL CONSENSUS TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 101800Z IS 16 FEET. NEXT WARNINGS AT 110300Z, 110900Z, 111500Z AND 112100Z. REFER TO TROPICAL CYCLONE 02S (BONGOYO) WARNINGS (WTXS31 PGTW) FOR TWELVE-HOURLY UPDATES.// NNNN