WTIO31 PGTW 300900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 04B (FOUR) WARNING NR 003// RMKS/ 1. TROPICAL CYCLONE 04B (FOUR) WARNING NR 003 01 ACTIVE TROPICAL CYCLONE IN NORTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 300600Z --- NEAR 9.3N 85.0E MOVEMENT PAST SIX HOURS - 320 DEGREES AT 12 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT REPEAT POSIT: 9.3N 85.0E --- FORECASTS: 12 HRS, VALID AT: 301800Z --- 10.2N 83.1E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 290 DEG/ 08 KTS --- 24 HRS, VALID AT: 010600Z --- 10.7N 81.5E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 280 DEG/ 08 KTS --- 36 HRS, VALID AT: 011800Z --- 11.0N 79.8E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 275 DEG/ 09 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 020600Z --- 11.2N 78.0E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 300900Z POSITION NEAR 9.5N 84.5E. TROPICAL CYCLONE (TC) 04B (FOUR), LOCATED APPROXIMATELY 822 NM SOUTH- SOUTHWEST OF CALCUTTA, INDIA, HAS TRACKED NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC) WITH DEEP CONVECTION DISPLACED SLIGHTLY WEST OF CENTER DUE TO MODERATE (20-25 KNOT) EASTERLY VERTICAL WIND SHEAR. A RECENT 300343Z ASCAT PASS SHOWED A WELL DEFINED BUT SLIGHTLY ELONGATED LLCC WITH 40 TO 45 KNOT WINDS LOCATED ALONG THE SOUTHERN PERIPHERY. THE CURRENT POSITION AND INTENSITY IS BASED ON THE ASCAT PASS WITH GOOD CONFIDENCE AND IS SUPPORTED BY DVORAK INTENSITY ESTIMATES OF T3.5 (45 KNOTS) FROM PGTW AND KNES. UPPER LEVEL ANALYSIS INDICATES A MARGINAL ENVIRONMENT DUE TO THE MODERATE VERTICAL WIND SHEAR; HOWEVER, THE SHEAR VECTOR IS IN-PHASE WITH THE STORM MOTION WHICH IS LIMITING ITS IMPACTS. GOOD DIVERGENCE ALOFT AND WARM SEA SURFACE TEMPERATURES ARE ALLOWING FOR THE RECENT INTENSIFICATION. THE CYCLONE IS TRACKING ALONG THE SOUTHERN PERIPHERY OF A DEEP LAYER SUBTROPICAL RIDGE TO THE NORTH. THIS RIDGE WILL REMAIN THE DOMINANT STEERING MECHANISM THROUGHOUT THE FORECAST PERIOD, DRIVING THE CYCLONE WESTWARD TOWARDS SOUTHERN INDIA. EXPECT ENVIRONMENTAL CONDITIONS TO REMAIN MARGINAL WHICH WILL SUPPORT A PERIOD OF INTENSIFICATION AS THE SYSTEM NEARS THE EASTERN COAST OF INDIA AND MAKES LANDFALL NEAR TAU 36. AFTERWARDS, TC 04B WILL MOVE INLAND AND FULLY DISSIPATE DUE TO INTERACTION WITH THE RUGGED TERRAIN. THE REMNANTS OF TC 04B ARE EXPECTED TO EMERGE OVER THE ARABIAN SEA WITH SOME MODELS SHOWING SOME POTENTIAL FOR REINTENSIFICATION. DYNAMIC MODEL GUIDANCE REMAINS IN GOOD AGREEMENT WHICH PROVIDES HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 300600Z IS 18 FEET. NEXT WARNINGS AT 301500Z, 302100Z, 010300Z AND 010900Z.//