WTXS31 PGTW 070900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 02S (BONGOYO) WARNING NR 001// REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/070321ZDEC2020// AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.// RMKS/ 1. TROPICAL CYCLONE 02S (BONGOYO) WARNING NR 001 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 070600Z --- NEAR 14.6S 81.9E MOVEMENT PAST SIX HOURS - 250 DEGREES AT 11 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT REPEAT POSIT: 14.6S 81.9E --- FORECASTS: 12 HRS, VALID AT: 071800Z --- 15.4S 80.0E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 235 DEG/ 10 KTS --- 24 HRS, VALID AT: 080600Z --- 16.5S 78.2E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 225 DEG/ 08 KTS --- 36 HRS, VALID AT: 081800Z --- 17.7S 77.0E 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 020 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 220 DEG/ 06 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 090600Z --- 18.6S 76.2E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 260 DEG/ 06 KTS --- 72 HRS, VALID AT: 100600Z --- 19.1S 73.6E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 275 DEG/ 10 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 110600Z --- 18.6S 69.5E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 275 DEG/ 10 KTS --- 120 HRS, VALID AT: 120600Z --- 18.2S 65.1E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 070900Z POSITION NEAR 14.8S 81.4E. 07DEC20. TROPICAL CYCLONE (TC) 02S (BONGOYO), LOCATED APPROXIMATELY 713 NM SOUTHEAST OF DIEGO GARCIA, HAS TRACKED WEST-SOUTHWESTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP CONVECTIVE BANDING WRAPPING INTO A WELL-DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC), WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE. A 070414Z MHS 89GHZ MICROWAVE IMAGE REVEALS CONVECTIVE BANDING, PRIMARILY, OVER THE SOUTHERN SEMICIRCLE WITH WEAK BANDING WRAPPING INTO THE NORTH QUADRANT AROUND A DEFINED LLCC. CONSEQUENTLY, A 070414Z ASCAT-B IMAGE SHOWS GALE-FORCE WINDS (35-40 KNOTS) OVER THE SOUTHERN SEMICIRCLE WITH 20-25 KNOT WINDS OVER THE NORTHERN SEMICIRCLE. THE INITIAL INTENSITY IS ASSESSED AT 35 KNOTS BASED ON THIS ASCAT DATA AS WELL AS A PGTW DVORAK ESTIMATE OF T2.5 (35 KNOTS). UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH ENHANCED POLEWARD OUTFLOW, LOW VERTICAL WIND SHEAR (VWS) AND WARM SST (28C). TC 02S IS FORECAST TO TRACK WEST-SOUTHWESTWARD THROUGH TAU 24 BUT SHOULD TURN SOUTHWESTWARD THROUGH TAU 60 AS A DEEP MIDLATITUDE SHORTWAVE TROUGH APPROACHES AND ERODES THE SUBTROPICAL RIDGE (STR). AFTER TAU 60, THE TROUGH WILL PROPAGATE EASTWARD AND A STRONG STR WILL BUILD TO THE SOUTH DRIVING TC 02S WESTWARD THROUGH TAU 120. NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT LENDING MODERATE CONFIDENCE IN THE JTWC FORECAST TRACK. TC 02S WILL INTENSIFY THROUGH TAU 48 TO A PEAK INTENSITY OF 55 KNOTS BUT IS EXPECTED TO WEAKEN STEADILY THROUGH THE REMAINDER OF THE FORECAST PERIOD. INCREASING VWS, SLIGHTLY COOLER SST (26C) AND WEAK BAROCLINICITY AFTER TAU 72 WILL SUPPORT DISSIPATION BY TAU 120. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 070600Z IS 12 FEET. NEXT WARNINGS AT 072100Z AND 080900Z. 2. THIS CANCELS AND SUPERSEDES REF A (WTXS21 PGTW 070330).// NNNN