WTXS32 PGTW 082100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 04S (IRVING) WARNING NR 012// RMKS/ 1. TROPICAL CYCLONE 04S (IRVING) WARNING NR 012 02 ACTIVE TROPICAL CYCLONES IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 081800Z --- NEAR 19.1S 76.8E MOVEMENT PAST SIX HOURS - 240 DEGREES AT 15 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 095 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 205 NM SOUTHEAST QUADRANT 185 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT REPEAT POSIT: 19.1S 76.8E --- FORECASTS: 12 HRS, VALID AT: 090600Z --- 21.2S 73.9E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 230 NM SOUTHEAST QUADRANT 200 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 225 DEG/ 19 KTS --- 24 HRS, VALID AT: 091800Z --- 23.8S 71.0E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 005 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 195 NM NORTHEAST QUADRANT 215 NM SOUTHEAST QUADRANT 180 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 205 DEG/ 18 KTS --- 36 HRS, VALID AT: 100600Z --- 27.1S 69.2E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 145 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 175 DEG/ 23 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 101800Z --- 31.7S 69.8E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 230 NM NORTHEAST QUADRANT 205 NM SOUTHEAST QUADRANT 190 NM SOUTHWEST QUADRANT 160 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 155 DEG/ 31 KTS --- 72 HRS, VALID AT: 111800Z --- 42.9S 76.7E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 260 NM NORTHEAST QUADRANT 345 NM SOUTHEAST QUADRANT 475 NM SOUTHWEST QUADRANT 490 NM NORTHWEST QUADRANT --- REMARKS: 082100Z POSITION NEAR 19.6S 76.1E. TROPICAL CYCLONE 04S (IRVING), LOCATED APPROXIMATELY 762 NM SOUTH-SOUTHEAST OF DIEGO GARCIA, HAS TRACKED WEST-SOUTHWESTWARD AT 15 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS CENTRALLY LOCATED PERSISTENT DEEP CONVECTION OCCLUDING A LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS BASED ON A 081604Z METOP-A ASCAT IMAGE SHOWING A CLEARLY DEFINED LLCC. THE INITIAL INTENSITY OF 90 KNOTS IS BASED ON DVORAK INTENSITY ESTIMATES OF T5.0 (90 KNOTS) FROM PGTW AND KNES. THE INITIAL INTENSITY IS ALSO SUPPORTED BY A RECENT SATCON ESTIMATE OF 91 KNOTS. ENVIRONMENTAL ANALYSIS REVEALS MODERATE (15 TO 20 KNOT) VERTICAL WIND SHEAR AND WARM SEA SURFACE TEMPERATURES (26 TO 27 DEGREES CELSIUS). UPPER LEVEL ANALYSIS SHOWS THE SYSTEM HAS A WELL DEFINED POLEWARD OUTFLOW CHANNEL. TC 04S IS TRACKING SOUTHWESTWARD ALONG THE NORTHWESTERN EXTENT OF THE SUBTROPICAL RIDGE (STR) LOCATED TO THE SOUTHEAST. THE SYSTEM IS FORECAST TO CONTINUE TO TRACK SOUTHEAST THROUGH TAU 36 AT WHICH TIME IT WILL ROUND THE RIDGE AXIS TURNING SOUTHWARD INITIALLY, BEFORE IT ACCELERATES TO THE SOUTHEAST. AROUND TAU 48, TC IRVING WILL BEGIN TO INTERACT WITH THE MID- LATITUDE WESTERLIES AND START EXTRA-TROPICAL TRANSITION (ETT). TC IRVING IS FORECAST TO COMPLETE ETT BY TAU 72 WHEN IT BECOMES EMBEDDED WITHIN THE MID-LATITUDE WESTERLIES AND TAKES ON FRONTAL CHARACTERISTICS. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT THROUGH TAU 72, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 081800Z IS 29 FEET. NEXT WARNINGS AT 090300Z, 090900Z, 091500Z AND 092100Z. REFER TO TROPICAL CYCLONE 03S (AVA) WARNINGS (WTXS31 PGTW) FOR SIX-HOURLY UPDATES.//