WTPS31 PGTW 052100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 009// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 009 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 051800Z --- NEAR 13.5S 164.3E MOVEMENT PAST SIX HOURS - 280 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 060 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 - 040 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT REPEAT POSIT: 13.5S 164.3E --- FORECASTS: 12 HRS, VALID AT: 060600Z --- 13.5S 163.8E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 215 DEG/ 04 KTS --- 24 HRS, VALID AT: 061800Z --- 14.1S 163.4E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 180 DEG/ 05 KTS --- 36 HRS, VALID AT: 070600Z --- 15.1S 163.4E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 185 NM NORTHEAST QUADRANT 185 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 165 DEG/ 06 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 071800Z --- 16.3S 163.7E MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 135 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 155 DEG/ 06 KTS --- 72 HRS, VALID AT: 081800Z --- 18.6S 164.8E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 135 DEG/ 07 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 091800Z --- 20.7S 167.0E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 135 DEG/ 09 KTS --- 120 HRS, VALID AT: 101800Z --- 23.2S 169.8E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT --- REMARKS: 052100Z POSITION NEAR 13.5S 164.2E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 342 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED WESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THE SYSTEM HAS DEVELOPED A CENTRAL COLD COVER (CCC) SIGNATURE, WITH DEEP CONVECTION EMBEDDED WITHIN A BROADER CIRRUS SHIELD. WHILE THE INITIAL POSITION IS NOT CLEAR IN THE INFRARED AND MULTISPECTRAL IMAGERY, MICROWAVE IMAGERY AT 89 AND 37 GHZ FROM A 051637Z SSMIS PASS CONFIRM DEVELOPMENT OF A MICROWAVE EYE FEATURE OVER THE PAST SIX HOURS, PROVIDING HIGH CONFIDENCE IN THE INITIAL POSITION. THE INITIAL INTENSITY IS BASED ON ASSESSMENT OF REPORTING AGENCY AND AUTOMATED DVORAK CURRENT INTENSITY ESTIMATES BETWEEN 4.5 AND 5.0. ENVIRONMENTAL ANALYSIS INDICATES THE SYSTEM RESIDES IN A WEAKLY FAVORABLE ENVIRONMENT WITH WARM SSTS NEAR 29 CELSIUS AND A STRONG POLEWARD OUTFLOW CHANNEL. VERTICAL WIND SHEAR (VWS) VALUES ARE MODERATE BETWEEN 20-25 KNOTS, BUT IS MOSTLY OFFSET BY THE OUTFLOW AND THE STORM MOTION THAT IS IN- PHASE WITH THE UPPER LEVEL WIND FLOW. OVER THE PAST 12 HOURS, TC DONNA HAS TRACKED WEST-NORTHWESTWARD IN RESPONSE TO DEVELOPMENT OF AN EXTENSION OF THE SUBTROPICAL RIDGE (STR) ALONG A TONGA TO NEW CALEDONIA AXIS, WHICH HAS BLOCKED DONNA?S MOVEMENT TO THE SOUTH. THE GENERAL WEST-NORTHWEST TRACK IS FORECAST TO CONTINUE THROUGH TAU 12. BY TAU 24, THE EXTENSION OF THE STR WILL WEAKEN WHILE THE STR AXIS WILL REORIENT TO A MORE NORTH-SOUTH ORIENTATION, ALLOWING TC DONNA TO BEGIN IT?S POLEWARD TURN AND ACCELERATE THROUGH THE REMAINDER OF THE FORECAST PERIOD. FAVORABLE UPPER-LEVEL CONDITIONS ARE FORECAST TO PERSIST THROUGH ABOUT TAU 48, THE SYSTEM IS FORECAST TO CONTINUE SLOW INTENSIFICATION, PEAKING AT 115 KNOTS AT TAU 48. THEREAFTER TC DONNA WILL WEAKEN RELATIVELY RAPIDLY DUE TO INCREASING VWS, AND DECREASING SEA SURFACE TEMPERATURES, BEGINNING EXTRA-TROPICAL TRANSITION BY TAU 120. NUMERICAL MODEL GUIDANCE IS IN OVERALL GOOD AGREEMENT WITH EGRR AS THE SOLE EASTWARD OUTLIER AND GFDN AS THE WESTERN OUTLIER. THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 051800Z IS 30 FEET. NEXT WARNINGS AT 060300Z, 060900Z, 061500Z AND 062100Z.//