WTXS31 PGTW 230900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 12S (CALEB) WARNING NR 001// RMKS/ 1. TROPICAL CYCLONE 12S (CALEB) WARNING NR 001 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 230600Z --- NEAR 12.4S 100.6E MOVEMENT PAST SIX HOURS - 145 DEGREES AT 10 KTS POSITION ACCURATE TO WITHIN 020 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 12.4S 100.6E --- FORECASTS: 12 HRS, VALID AT: 231800Z --- 13.4S 101.3E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 155 DEG/ 05 KTS --- 24 HRS, VALID AT: 240600Z --- 14.3S 101.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 160 DEG/ 04 KTS --- 36 HRS, VALID AT: 241800Z --- 15.0S 102.0E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 205 DEG/ 01 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 250600Z --- 15.2S 101.9E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 260 DEG/ 01 KTS --- 72 HRS, VALID AT: 260600Z --- 15.3S 101.4E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 280 DEG/ 03 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 270600Z --- 15.1S 100.3E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 285 DEG/ 03 KTS --- 120 HRS, VALID AT: 280600Z --- 14.8S 99.3E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT --- REMARKS: 230900Z POSITION NEAR 12.7S 100.8E. TROPICAL CYCLONE 12S (CALEB), LOCATED APPROXIMATELY 215 NM EAST OF COCOS ISLAND, HAS TRACKED SOUTHEASTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC), LENDING HIGH CONFIDENCE TO THE INITIAL POSITION, WITH DEEP FLARING CENTRAL CONVECTION. THE INITIAL INTENSITY OF 40 KNOTS IS BASED ON A 230309Z METOP-B ASCAT IMAGE SHOWING A SLIGHTLY ELONGATED LLCC WITH EVIDENT 40 KNOT BARBS ON THE NORTHWESTERN AND SOUTHWESTERN PERIPHERIES. UPPER-LEVEL ANALYSIS SHOWS AN IMPROVING OUTFLOW SITUATION WITH HIGH DIFFLUENCE ON THE WESTERN PERIPHERY AND A WELL ESTABLISHED POLEWARD CHANNEL, HOWEVER THE PREVAILING EASTERLY FLOW IS DISPLACING THE DEEP CONVECTION OFF TO THE WEST. THE EASTERLY WINDS ALOFT ARE EXPECTED TO WEAKEN SLIGHTLY OVER THE NEXT 24 HOURS ALLOWING FOR TC CALEB TO INTENSIFY TO 45 KNOTS, BUT THE HIGH WIND SHEAR WILL PERSIST THROUGHOUT THE FORECAST PERIOD LIMITING THE POTENTIAL FOR FURTHER INTENSIFICATION. CURRENTLY A MID TO LOW LEVEL NEAR-EQUATORIAL RIDGE (NER) IS DRIVING THE SYSTEM ON A SOUTHWESTWARD TRACK. BY TAU 36 ANOTHER SUBTROPICAL RIDGE TO THE SOUTH WILL START TO BUILD, COMPETING WITH THE NER PLACING TC CALEB INTO A QUASI- STATIONARY TRACK. BY TAU 72 THE SOUTHERN RIDGE WILL ASSUME STEERING, DRIVING THE SYSTEM ON A GENERALLY WESTWARD TRACK. DYNAMIC MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT FOR THE FIRST 36 HOURS, HOWEVER SOLUTIONS BEGIN TO DIVERGE THEREAFTER AS THE SYSTEM ENTERS THE WEAK STEERING ENVIRONMENT WITH INCREASING UNCERTAINTY IN THE POSITION AND TIMING OF THE TURN TO THE WEST. OVERALL THERE IS LOW CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 230600Z IS 13 FEET. NEXT WARNINGS AT 232100Z AND 240900Z.//