SUBJ/TROPICAL CYCLONE 13S (THIRTEEN) WARNING NR 010// MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// RMKS/ WTXS31 PGTW 251500 1. TROPICAL CYCLONE 13S (THIRTEEN) WARNING NR 010 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 251200Z --- NEAR 17.6S 95.4E MOVEMENT PAST SIX HOURS - 230 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 040 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 - 045 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT REPEAT POSIT: 17.6S 95.4E --- FORECASTS: 12 HRS, VALID AT: 260000Z --- 18.0S 94.9E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 250 DEG/ 05 KTS --- 24 HRS, VALID AT: 261200Z --- 18.3S 94.0E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 265 DEG/ 07 KTS --- 36 HRS, VALID AT: 270000Z --- 18.4S 92.6E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 275 DEG/ 09 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 271200Z --- 18.2S 90.8E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 280 DEG/ 12 KTS --- 72 HRS, VALID AT: 281200Z --- 17.3S 86.0E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 275 DEG/ 12 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 291200Z --- 16.6S 80.9E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 160 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 280 DEG/ 12 KTS --- 120 HRS, VALID AT: 301200Z --- 15.6S 76.0E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 200 NM NORTHWEST QUADRANT --- REMARKS: 251500Z POSITION NEAR 17.7S 95.3E. 25JAN21. TROPICAL CYCLONE (TC) 13S (THIRTEEN), LOCATED APPROXIMATELY 340 NM SOUTH-SOUTHWEST OF COCOS ISLANDS, AUSTRALIA, HAS TRACKED SOUTHWESTWARD AT 06 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THAT FLARING CONVECTION HAS PERSISTED OVER THE PAST TWELVE HOURS. HOWEVER, THE CENTRAL CONVECTION HAS REMAINED OVER THE LOW LEVEL CIRCULATION (LLC) FOR THE PAST SIX HOURS DUE TO THE DECREASING VERTICAL WIND SHEAR (VWS). THE INITIAL POSITION IS PLACED WITH GOOD CONFIDENCE BASED ON LOW CLOUD TRACING IN MSI AND THE LLC FEATURES EVIDENT IN A 251235Z SSMIS 91 GHZ MICROWAVE IMAGE. ASSESSED AT 35 KTS, THE INITIAL INTENSITY IS DERIVED FROM OBJECTIVE AND SUBJECTIVE DVORAK ESTIMATES OF T1.5-2.9 (25-43 KTS) AND IS SUPPORTED BY THE IMPROVED OVERHEAD CONVECTION AT SYNOPTIC TIME. UPPER LEVEL ANALYSIS DEPICTS MODERATE (15-20 KTS) VWS, FAIR WESTWARD OUTFLOW, AND A DEVELOPING POLEWARD OUTFLOW CHANNEL. SEA SURFACE TEMPERATURES (SST) REMAIN CONDUCIVE AT 27 CELSIUS. TC 13S IS TRACKING ALONG A SOUTHWEST EXTENSION OF A NEAR EQUATORIAL RIDGE TO THE EAST AND IS EXPECTED TO CONTINUE ALONG THE PERIPHERY THROUGH TAU 24. AFTERWARDS, A BUILDING SUBTROPICAL RIDGE TO THE SOUTHWEST WILL TAKE OVER AS THE PRIMARY STEERING INFLUENCE, DRIVING THE SYSTEM WESTWARD THEN WEST-NORTHWESTWARD THROUGH THE REMAINDER OF THE FORECAST. THE CURRENT ENVIRONMENT WILL ALLOW FOR LIMITED INTENSIFICATION TO 40 KTS BY TAU 24. THEN, INCREASING VWS WILL IMPACT THE SYSTEM AS IT TRANSITS WESTWARD, TEMPERING THE INTENSITY TO 35 KTS. NEAR THE END OF THE FORECAST, TC 13S SHOULD SLOWLY MOVE EQUATORWARD AND INTO WARMER (28 CELSIUS) SST, ALLOWING FOR A PERIOD OF INTENSIFICATION TO 45 KTS. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THE EXCEPTION OF THE NAVGEM SOLUTION WHICH DEPICTS A SHARP WEST-NORTHWESTWARD TURN AFTER TAU 12. OVERALL, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST WHICH IS PLACED NEAR THE MULTI-MODEL CONSENSUS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 251200Z IS 13 FEET. NEXT WARNINGS AT 260300Z AND 261500Z.// NNNN