WTIO31 PGTW 210300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 01B (ROANU) WARNING NR 012// RMKS/ 1. TROPICAL CYCLONE 01B (ROANU) WARNING NR 012 01 ACTIVE TROPICAL CYCLONE IN NORTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 210000Z --- NEAR 20.7N 89.2E MOVEMENT PAST SIX HOURS - 060 DEGREES AT 18 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 125 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 20.7N 89.2E --- FORECASTS: 12 HRS, VALID AT: 211200Z --- 22.7N 92.1E 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 24 HR POSIT: 050 DEG/ 17 KTS --- 24 HRS, VALID AT: 220000Z --- 24.8N 95.0E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 210300Z POSITION NEAR 21.2N 89.9E. TROPICAL CYCLONE 01B (ROANU), LOCATED APPROXIMATELY 174 NM WEST- SOUTHWEST OF CHITTAGONG, HAS TRACKED EAST-NORTHEASTWARD AT 18 KNOTS OVER THE PAST SIX HOURS. THE CURRENT POSITION IS BASED ON RECENT MICROWAVE SATELLITE IMAGERY INCLUDING A 202214Z SSMIS PASS. THE INTENSITY OF 50 KNOTS IS CONSISTENT WITH SUBJECTIVE DVORAK AND AUTOMATED SATELLITE INTENSITY ESTIMATES FROM MULTIPLE REPORTING AGENCIES AND EARLIER SCATTEROMETER DATA. CONVECTIVE ORGANIZATION HAS IMPROVED SLIGHTLY OVER THE PAST SIX HOURS, WITH DEEP CONVECTION CONTINUING TO WRAP AROUND THE NORTH SIDE OF THE CIRCULATION AND INTO THE CENTER. TC 01B IS ACCELERATING EAST-NORTHEASTWARD UNDER THE STRONG STEERING INFLUENCE OF LOW- TO MID-LEVEL SOUTHWESTERLY MONSOON FLOW. DYNAMICAL MODELS REMAIN IN GOOD AGREEMENT REGARDING THE FORECAST TRACK, WHICH LIES CLOSE TO THE PREVIOUS FORECAST WITH HIGH CONFIDENCE. TC 01B IS EXPECTED TO PASS THROUGH A MARGINALLY- FAVORABLE ENVIRONMENT AS IT APPROACHES LANDFALL DUE TO ENHANCED POLEWARD OUTFLOW UNDER A SUBTROPICAL RIDGE ALOFT, WARM SEA-SURFACE TEMPERATURES, AND WEAK TO MODERATE VERTICAL WIND SHEAR OF 10-20 KNOTS. THE SYSTEM MAY INTENSIFY SLIGHTLY PRIOR TO LANDFALL, WHICH IS ANTICIPATED TO OCCUR BEFORE TAU 12. INCREASING VERTICAL WIND SHEAR INDUCED BY MID-LATITUDE WESTERLIES AND PASSAGE OVER LAND WILL YIELD STEADY WEAKENING AND DISSIPATION BY TAU 24. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210000Z IS 18 FEET. NEXT WARNINGS AT 210900Z, 211500Z AND 212100Z.//