WTIO31 PGTW 170300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 01A (ONE) WARNING NR 002// RMKS/ 1. TROPICAL CYCLONE 01A (ONE) WARNING NR 002 01 ACTIVE TROPICAL CYCLONE IN NORTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 170000Z --- NEAR 13.1N 48.9E MOVEMENT PAST SIX HOURS - 260 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 040 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 - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT REPEAT POSIT: 13.1N 48.9E --- FORECASTS: 12 HRS, VALID AT: 171200Z --- 12.9N 47.9E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 250 DEG/ 06 KTS --- 24 HRS, VALID AT: 180000Z --- 12.5N 46.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 245 DEG/ 06 KTS --- 36 HRS, VALID AT: 181200Z --- 12.0N 45.6E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 245 DEG/ 05 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 190000Z --- 11.5N 44.6E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 075 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 240 DEG/ 05 KTS --- 72 HRS, VALID AT: 200000Z --- 10.6N 43.0E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 170300Z POSITION NEAR 13.0N 48.6E. TROPICAL CYCLONE 01A (ONE), LOCATED APPROXIMATELY 229 NM EAST OF ADEN, YEMEN, HAS TRACKED WESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. THE CURRENT POSITION IS BASED, WITH FAIR CONFIDENCE, ON LOW- LEVEL TURNING EVIDENT IN A 162143Z AMSR2 PASS AND A 170000Z INFRARED SATELLITE IMAGERY FIX FROM PGTW. THE INTENSITY OF 40 KNOTS IS SET SLIGHTLY ABOVE RECENT DVORAK INTENSITY ESTIMATES OF T2.5 FROM PGTW AND KNES BASED ON THE IMPROVING CONVECTIVE BANDING STRUCTURE. TC 01A HAS TURNED WESTWARD OVER THE PAST SIX HOURS UNDER THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE (STR) TO THE NORTH AND LOW TO MID-LEVEL FLOW FOLLOWING THE COASTAL TERRAIN. THE SYSTEM IS EXPECTED TO TURN SOUTHWESTWARD DURING THE FORECAST PERIOD UNDER THE CONTINUOUS INFLUENCE OF THESE STEERING FEATURES. THE ENVIRONMENT IS FAVORABLE FOR ADDITIONAL INTENSIFICATION IN THE NEAR-TERM, WITH WARM ALONG-TRACK SEA SURFACE TEMPERATURES (ABOUT 30C), LOW VERTICAL WIND SHEAR(10-15 KNOTS) AND A SUPPORTIVE POLEWARD UPPER-LEVEL OUTFLOW PATTERN. A CONSTRAINED INFLOW PATTERN RESULTING FROM THE PROXIMITY TO LAND AND A LESS FAVORABLE UPPER- LEVEL FLOW PATTERN ARE EXPECTED TO HALT THIS INTENSIFICATION TREND AND LEAD TO SLOW WEAKENING AFTER TAU 24.IT IS ALSO WORTH NOTING THAT SMALL DEVIATIONS IN THE TRACK COULD RESULT IN SIGNIFICANT INTENSITY CHANGES DUE TO POTENTIAL LAND INTERACTION. NUMERICAL MODEL TRACK FORECAST GUIDANCE IS IN GOOD OVERALL AGREEMENT AND THE SYNOPTIC STEERING PATTERN IS RELATIVELY STRAIGHTFORWARD, LENDING HIGH CONFIDENCE TO THE CURRENT JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 170000Z IS 11 FEET.NEXT WARNINGS AT 170900Z, 171500Z, 172100Z AND 180300Z.//