WTIO31 PGTW 310300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 04A (CHAPALA) WARNING NR 010// RMKS/ 1. TROPICAL CYCLONE 04A (CHAPALA) 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: 310000Z --- NEAR 13.9N 59.6E MOVEMENT PAST SIX HOURS - 270 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 010 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT REPEAT POSIT: 13.9N 59.6E --- FORECASTS: 12 HRS, VALID AT: 311200Z --- 13.9N 58.2E MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 275 DEG/ 08 KTS --- 24 HRS, VALID AT: 010000Z --- 14.0N 56.5E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 280 DEG/ 08 KTS --- 36 HRS, VALID AT: 011200Z --- 14.2N 54.9E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 285 DEG/ 07 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 020000Z --- 14.6N 53.5E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 295 DEG/ 07 KTS --- 72 HRS, VALID AT: 030000Z --- 15.9N 50.8E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND VECTOR TO 96 HR POSIT: 315 DEG/ 08 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 040000Z --- 18.2N 48.4E MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 310300Z POSITION NEAR 13.9N 59.3E. TROPICAL CYCLONE (TC) 04A (CHAPALA), LOCATED APPROXIMATELY 393 NM SOUTH OF MASIRAH ISLAND, HAS TRACKED WESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A RAGGED PINHOLE EYE WITH A STRUGGLING CONVECTIVE STRUCTURE AS THE CYCLONE HAS BECOME MORE ASYMMETRIC OVER THE PAST SIX HOURS. A 302059Z AMSR-2 89GHZ MICROWAVE IMAGE SHOWS SIGNIFICANT CONVECTION REMAINS AROUND THE CORE, SPECIFICALLY ALONG THE NORTHERN AND WESTERN QUADRANTS. WATER VAPOR IMAGERY AND THE TOTAL PRECIPITABLE WATER LOOP SHOWS DRY AIR PULLING INTO THE CENTER OF THE CIRCULATION. THERE IS HIGH CONFIDENCE IN THE INITIAL POSITION BASED ON THE PINHOLE EYE. THE CURRENT INTENSITY HAS BEEN DECREASED AS THE CONVECTIVE STRUCTURE BEGINS TO BREAK DOWN. THIS IS SUPPORTED BY DECLINING DVORAK INTENSITY ESTIMATES FROM ALL AGENCIES. ENVIRONMENTAL CONDITIONS REMAIN FAVORABLE WITH NEAR RADIAL OUTFLOW ENHANCED BY A TUTT CELL LOCATED OVER INDIA; HOWEVER, THE SYSTEM IS NOW ENCOUNTERING 10 TO 15 KNOT SOUTHERLY VERTICAL WIND SHEAR. TC 04A IS TRACKING ALONG THE SOUTHERN PERIPHERY OF A DEEP LAYERED SUB-TROPICAL RIDGE (STR) LOCATED OVER THE NORTHERN ARABIAN SEA AND IS EXPECTED TO CONTINUE TRACKING WESTWARD OVER THE NEXT 36 HOURS. TC CHAPALA WILL CONTINUE TO WEAKEN AS DRY AIR ENTRAINMENT FURTHER DETERIORATES THE SYSTEM. AFTERWARDS, THE CYCLONE WILL TRACK MORE POLEWARD AS IT ROUNDS THE SOUTHWESTERN PERIPHERY OF THE STR AND MAKES LANDFALL OVER CENTRAL YEMEN JUST BEFORE TAU 72. CONCURRENTLY, TC 04A WILL RAPIDLY DISSIPATE DUE TO LAND INTERACTION, LEADING TO ITS DISSIPATION BY THE END OF THE FORECAST PERIOD. DYNAMIC MODEL GUIDANCE REMAINS IN GOOD AGREEMENT, LENDING HIGH CONFIDENCE IN THE JTWC FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 310000Z IS 30 FEET. NEXT WARNINGS AT 310900Z, 311500Z, 312100Z AND 010300Z.//