WTIO31 PGTW 201500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 01B (ROANU) WARNING NR 010// RMKS/ 1. TROPICAL CYCLONE 01B (ROANU) WARNING NR 010 01 ACTIVE TROPICAL CYCLONE IN NORTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 201200Z --- NEAR 18.9N 87.0E MOVEMENT PAST SIX HOURS - 065 DEGREES AT 14 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 095 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT REPEAT POSIT: 18.9N 87.0E --- FORECASTS: 12 HRS, VALID AT: 210000Z --- 20.2N 89.5E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 095 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 050 DEG/ 15 KTS --- 24 HRS, VALID AT: 211200Z --- 22.1N 92.0E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND VECTOR TO 36 HR POSIT: 050 DEG/ 17 KTS --- 36 HRS, VALID AT: 220000Z --- 24.3N 94.9E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 201500Z POSITION NEAR 19.2N 87.6E. TROPICAL CYCLONE (TC) 01B (ROANU), LOCATED APPROXIMATELY 338 NM SOUTHWEST OF CHITTAGONG, BANGLADESH, HAS TRACKED EAST- NORTHEASTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY INDICATES RAPIDLY DECAYING DEEP CONVECTION WITH FRAGMENTED BANDING WRAPPING INTO A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC). A 201224Z SSMIS 91GHZ IMAGE DEPICTS AN EXPOSED LLCC WITH TIGHTLY-WRAPPED SHALLOW BANDING WRAPPING INTO A DEFINED CENTER WITH FRAGMENTED CONVECTIVE BANDING OVER THE PERIPHERY OF THE LLCC. THE CURRENT INTENSITY REMAINS ASSESSED AT 50 KNOTS BASED ON AN AVERAGE OF DVORAK INTENSITY ESTIMATES OF T3.5 (55 KNOTS) AND AUTOMATED INTENSITY ESTIMATES OF T3.0 (45 KNOTS). TC 01B IS ACCELERATING NORTHEASTWARD ALONG THE NORTHWESTERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR) AND IS FORECAST TO CONTINUE TRACKING NORTHEASTWARD ALONG THE NORTHERN PERIPHERY OF THE STR THROUGH THE FORECAST PERIOD. DYNAMIC GUIDANCE REMAINS IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. TC 01B IS EXPECTED TO REMAIN WITHIN A MARGINALLY-FAVORABLE ENVIRONMENT WITH PERSISTENT MODERATE VWS, HAMPERING CONVECTIVE DEVELOPMENT, OFFSET BY ENHANCED POLEWARD OUTFLOW AND WARM SST. AFTER PEAKING AT TAU 12, TC 01B SHOULD BEGIN TO GRADUALLY WEAKEN AS IT INTERACTS WITH THE MIDLATITUDE WESTERLIES. THE SYSTEM WILL MAKE LANDFALL NEAR TAU 24 AND WILL DISSIPATE OVER LAND BY TAU 36. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 201200Z IS 18 FEET. NEXT WARNINGS AT 202100Z, 210300Z, 210900Z AND 211500Z.//