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Tropical Cyclone DONNA Southern Hemisphere Summary |
WTPS21 PGTW 20170501 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE FORMATION ALERT// RMKS/ 1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 120 NM EITHER SIDE OF A LINE FROM 12.5S 169.9E TO 14.6S 173.6E WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME. WINDS IN THE AREA ARE ESTIMATED TO BE 25 TO 30 KNOTS. METSAT IMAGERY AT 011800Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 12.7S 170.2E. THE SYSTEM IS MOVING EAST-SOUTHEASTWARD AT 06 KNOTS. 2. REMARKS: ANIMATED INFRARED/MULTI-SPECTRAL SATELLITE IMAGERY AND A 011909Z SSMIS 91 GHZ MICROWAVE PASS SHOWED DEEP, PERSISTENT AND FLARING CONVECTION WITH FRAGMENTED BANDING WRAPPING INTO A LOW-LEVEL CIRCULATION CENTER (LLCC). A 011032Z 25KM (METOP-B) PARTIAL ASCAT PASS REVEALS PRIMARIALLY 20-25 KNOT WINDS WITH A FEW 30 KNOT WIND BARBS AROUND THE EASTERN PERIPHERY OF AN EXTRAPOLATED LLCC. UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH A MODERATE POLEWARD OUTFLOW CHANNEL ASSOCIATED WITH A POINT SOURCE OVERHEAD AND LIGHT TO MODERATE (10-15 KNOTS) VERTICAL WIND SHEAR, IN ADDITION TO WARM SEA SURFACE TEMPERATURES (28-29 CELSIUS). GLOBAL MODELS ARE IN AGREEMENT THAT THE DISTURBANCE WILL TRACK EAST- SOUTHEASTWARD OVER THE NEXT COUPLE OF DAYS BEFORE HOOKING BACK TOWARD A SOUTHWESTWARD DIRECTION. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1000 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH. 3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 022100Z. ========================================================================= WTPS31 PGTW 20170502 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (EIGHTEEN) WARNING NR 001// REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/012051ZMAY2017// AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT// RMKS/ 1. TROPICAL CYCLONE 18P (EIGHTEEN) WARNING NR 001 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 021800Z --- NEAR 13.0S 171.9E MOVEMENT PAST SIX HOURS - 090 DEGREES AT 07 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 025 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT REPEAT POSIT: 13.0S 171.9E --- FORECASTS: 12 HRS, VALID AT: 030600Z --- 13.1S 172.1E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 270 DEG/ 01 KTS --- 24 HRS, VALID AT: 031800Z --- 13.1S 171.9E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 270 DEG/ 07 KTS --- 36 HRS, VALID AT: 040600Z --- 13.1S 170.5E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 265 DEG/ 05 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 041800Z --- 13.2S 169.5E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 245 DEG/ 04 KTS --- 72 HRS, VALID AT: 051800Z --- 14.0S 167.9E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 180 DEG/ 03 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 061800Z --- 15.1S 167.9E 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 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 155 DEG/ 05 KTS --- 120 HRS, VALID AT: 071800Z --- 17.0S 168.8E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 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 - 060 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 075 NM NORTHWEST QUADRANT --- REMARKS: 022100Z POSITION NEAR 13.0S 172.0E. TROPICAL CYCLONE 18P (EIGHTEEN), LOCATED APPROXIMATELY 484 NM NORTHWEST OF SUVA, FIJI, HAS TRACKED EASTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP CENTRAL CONVECTION WITH FORMATIVE BANDING SHOWING RAPID CONSOLIDATION OVER THE LAST SIX HOURS. THE INITIAL POSITION IS EXTRAPOLATED FROM A LOW REFLECTIVITY FEATURE OBSERVED IN A 021521Z 89 GHZ GMI IMAGE WITH HIGH CONFIDENCE. THE INITIAL INTENSITY ASSESSMENT OF 40 KNOTS IS BASED ON AN AVERAGE OF AVAILABLE SUBJECTIVE DVORAK ESTIMATES RANGING FROM T2.5 TO T3.0 (35 TO 45 KNOTS). ENVIRONMENTAL ANALYSIS SUGGESTS VERY FAVORABLE CONDITIONS WITH SSTS NEAR 30 CELSIUS AND OCEAN HEAT CONTENT RELATIVELY HIGH. A MIDLATITUDE TROUGH TO THE SOUTH IS PROVIDING EXCELLENT POLEWARD OUTFLOW, AND VERTICAL WIND SHEAR IS LOW. CURRENTLY TC 18P IS IN A WEAK STEERING ENVIRONMENT WITH WEAK MID-LEVEL RIDGES TO THE NORTHEAST AND WEST COMPETING FOR STEERING. A QUASI-STATIONARY TRACK IS FORECAST FOR THE NEXT 24 TO 36 HOURS WITH GRADUAL INTENSIFICATION EXPECTED WHILE OVER THE WARM WATER. AS THE TROUGH TO THE SOUTH PASSES THROUGH THE REGION OVER THE NEXT 24 HOURS, RIDGING WILL BUILD IN TO THE SOUTH ACCELERATING THE SYSTEM WESTWARD AROUND TAU 36. ANOTHER LONGWAVE TROUGH IS EXPECTED TO APPROACH FROM THE WEST AROUND TAU 72 PROVIDING ANOTHER PERIOD OF ENHANCED EXHAUST IN THE UPPER LEVELS. PEAK INTENSITY IS EXPECTED TO REACH 110 KNOTS BY TAU 96 AS THE SYSTEM ROUNDS THE RIDGE AXIS TURNING SOUTHWARD. NUMERICAL MODEL GUIDANCE SHOWS SIGNIFICANT SPREAD IN POSSIBLE TRACK MOTION DUE TO THE NEAR-TERM COMPLEX STEERING SCENARIO. OVERALL, EACH SOLUTION SHOWS AGREEMENT WITH THE TRACK PHILOSOPHY BUT VARIES IN THE EXACT POSITION AND TIMING OF THE TURNS. DUE TO THE COMPLEX MOTION OF THE SYSTEM, THERE IS LOW CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 021800Z IS 14 FEET. NEXT WARNINGS AT 030900Z AND 032100Z. THIS CANCELS AND SUPERSEDES REF A (WTPS21 PGTW 012100).// ========================================================================= WTPS31 PGTW 20170503 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 002// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 002 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 030600Z --- NEAR 12.7S 171.2E MOVEMENT PAST SIX HOURS - 280 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT REPEAT POSIT: 12.7S 171.2E --- FORECASTS: 12 HRS, VALID AT: 031800Z --- 12.7S 170.4E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 095 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 255 DEG/ 05 KTS --- 24 HRS, VALID AT: 040600Z --- 13.0S 169.4E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 245 DEG/ 05 KTS --- 36 HRS, VALID AT: 041800Z --- 13.5S 168.4E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 230 DEG/ 05 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 050600Z --- 14.1S 167.6E 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 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 180 DEG/ 03 KTS --- 72 HRS, VALID AT: 060600Z --- 15.2S 167.6E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 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 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 150 DEG/ 04 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 070600Z --- 16.6S 168.4E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 150 DEG/ 05 KTS --- 120 HRS, VALID AT: 080600Z --- 18.4S 169.5E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT --- REMARKS: 030900Z POSITION NEAR 12.7S 171.0E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 344 NM NORTH-NORTHEAST OF PORT VILA, VANUATU, HAS TRACKED WESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. THE CURRENT POSITION IS BASED ON A LOW-LEVEL CENTER FEATURE EVIDENT IN A 030412Z SSMIS IMAGE AND RECENT SATELLITE POSITION FIXES FROM KNES AND PGTW. THE INTENSITY OF 55 KNOTS IS CONSISTENT WITH DVORAK SATELLITE INTENSITY ESTIMATES OF T=3.5 FROM THE SAME REPORTING AGENCIES. TC 18P HAS TURNED WESTWARD OVER THE PAST SIX HOURS UNDER THE INFLUENCE OF A DEVELOPING SUBTROPICAL STEERING RIDGE TO THE SOUTH. THE SYSTEM HAS STEADILY INTENSIFIED, AND BECOME INCREASINGLY ORGANIZED, UNDER THE FAVORABLE INFLUENCES OF STRONG POLEWARD OUTFLOW ALOFT, LOW VERTICAL WIND SHEAR (5-10 KNOTS) AND PASSAGE OVER VERY WARM WATER (29-30C). TC 18P IS EXPECTED TO TRACK WESTWARD TO SOUTHWESTWARD OVER THE NEXT 48 HOURS UNDER THE CONTINUED INFLUENCE OF THE SUBTROPICAL STEERING RIDGE. STEADY INTENSIFICATION IS ANTICIPATED AS ENVIRONMENTAL CONDITIONS REMAIN FAVORABLE, WITH SOME GUIDANCE SUGGESTING THAT A MORE RAPID INTENSIFICATION RATE THAN INDICATED IN THE CURRENT FORECAST IS POSSIBLE. BY TAU 48, A BREAK IS EXPECTED TO DEVELOP IN THE STEERING RIDGE IN RESPONSE TO AN APPROACHING MID-LATITUDE TROUGH, ALLOWING TC 18P TO TURN SHARPLY POLEWARD AROUND THE STEERING RIDGE PERIPHERY. ADDITIONAL INTENSIFICATION IS EXPECTED INTO THE EXTENDED PERIOD, AS POLEWARD OUTFLOW IS ENHANCED AHEAD OF THE DEVELOPING MID-LATITUDE TROUGH. BY TAU 120, INCREASING VERTICAL WIND SHEAR ASSOCIATED WITH UPPER-LEVEL FLOW AHEAD OF THE TROUGH SHOULD INITIATE A WEAKENING TREND. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT REGARDING THE OVERALL FORECAST SCENARIO OF A WESTWARD TO SOUTHWESTWARD TRACK IN THE NEAR-TERM, FOLLOWED BY A POLEWARD TRACK IN THE MEDIUM TO EXTENDED RANGE. HOWEVER, THERE IS CONSIDERABLE DISAGREEMENT REGARDING THE EXACT PATH THE SYSTEM WILL FOLLOW. THE CURRENT JTWC OFFICIAL FORECAST IS SHIFTED SLIGHTLY WESTWARD FROM THE PREVIOUS FORECAST AND LIES WITHIN THE MODEL FORECAST ENVELOPE NOT FAR FROM THE MULTI-MODEL CONSENSUS, WHICH HAS CONSISTENTLY INDICATED A TRACK RUNNING PARALLEL AND NEAR TO THE VANUATU ISLAND CHAIN. CONSIDERING THE LARGE MODEL SPREAD, THERE IS LOW CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 030600Z IS 18 FEET. NEXT WARNINGS AT 032100Z AND 040900Z.// ========================================================================= WTPS31 PGTW 20170503 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 003// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 003 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 031800Z --- NEAR 12.9S 169.6E MOVEMENT PAST SIX HOURS - 265 DEGREES AT 09 KTS POSITION ACCURATE TO WITHIN 025 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT REPEAT POSIT: 12.9S 169.6E --- FORECASTS: 12 HRS, VALID AT: 040600Z --- 13.2S 168.7E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 250 DEG/ 05 KTS --- 24 HRS, VALID AT: 041800Z --- 13.6S 167.7E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 230 DEG/ 05 KTS --- 36 HRS, VALID AT: 050600Z --- 14.2S 166.9E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 205 DEG/ 05 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 051800Z --- 15.1S 166.5E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 170 DEG/ 03 KTS --- 72 HRS, VALID AT: 061800Z --- 16.2S 166.7E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 145 DEG/ 04 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 071800Z --- 17.6S 167.7E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 140 DEG/ 06 KTS --- 120 HRS, VALID AT: 081800Z --- 19.4S 169.4E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT --- REMARKS: 032100Z POSITION NEAR 13.0S 169.4E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 298 NM NORTH- NORTHEAST OF PORT VILA, VANUATU, HAS TRACKED WESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP CONVECTIVE ACTIVITY SHOWING IMPROVED CONSOLIDATION OVER THE LAST SIX HOURS. THE INITIAL POSITION IS PLACED WITH GOOD CONFIDENCE BASED ON A CIRCULATION FEATURE OBSERVED IN AN 031842Z 91 GHZ SSMIS IMAGE. THE INITIAL INTENSITY ASSESSMENT OF 65 KNOTS IS BASED ON A COMBINATION OF OBJECTIVE AND SUBJECTIVE DVORAK ESTIMATES OF T4.0 (65 KNOTS). ENVIRONMENTAL ANALYSIS SHOWS A VERY FAVORABLE ENVIRONMENT WITH WARM SSTS NEAR 30 CELSIUS, AND VERY GOOD OUTFLOW ALOFT. AN UPPER-LEVEL POINT SOURCE WAS ANALYZED JUST EAST OF THE SYSTEM WHICH IS CREATING A SLIGHT SHEAR ENVIRONMENT WITH RESTRICTED OUTFLOW ON THE EASTERN SIDE, HOWEVER THE SYSTEM IS TRACKING IN PHASE WITH THE DIRECTION OF THE SHEAR VECTOR. CURRENTLY TC DONNA IS TRACKING WESTWARD GUIDED BY A BUILDING SUBTROPICAL RIDGE TO THE SOUTH. FURTHER INTENSIFICATION IS EXPECTED OVER THE FORECAST PERIOD DUE TO THE FAVORABLE CONDITIONS. PEAK INTENSITY IS EXPECTED TO REACH 110 KNOTS BY TAU 72 DUE TO ENHANCED OUTFLOW INTO AN APPROACHING TROUGH BEGINNING AROUND TAU 48. THE APPROACHING TROUGH WILL WEAKEN THE WESTERN EDGE OF THE STEERING RIDGE, CAUSING TC DONNA TO TURN SOUTHWARD AROUND TAU 48. NUMERICAL MODEL GUIDANCE SHOWS GENERAL AGREEMENT WITH THE FORECAST SCENARIO, HOWEVER THERE IS STILL A GREAT DEGREE OF VARIABILITY IN TRACK MOTION. THE FORECAST TRACK IS PLACED NEAR THE MULTI-MODEL CONSENSUS, BUT DUE TO THE SPREAD IN AVAILABLE MODEL GUIDANCE THERE IS OVERALL LOW CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 031800Z IS 22 FEET. NEXT WARNINGS AT 040900Z AND 042100Z.// ========================================================================= WTPS31 PGTW 20170504 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 004// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 004 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 040600Z --- NEAR 12.4S 168.1E MOVEMENT PAST SIX HOURS - 280 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 015 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT REPEAT POSIT: 12.4S 168.1E --- FORECASTS: 12 HRS, VALID AT: 041800Z --- 12.8S 167.1E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 235 DEG/ 05 KTS --- 24 HRS, VALID AT: 050600Z --- 13.4S 166.2E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 210 DEG/ 04 KTS --- 36 HRS, VALID AT: 051800Z --- 14.1S 165.8E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 180 DEG/ 03 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 060600Z --- 14.7S 165.8E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 165 DEG/ 03 KTS --- 72 HRS, VALID AT: 070600Z --- 15.9S 166.1E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 150 DEG/ 06 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 080600Z --- 18.0S 167.3E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 145 DEG/ 06 KTS --- 120 HRS, VALID AT: 090600Z --- 19.9S 168.8E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT --- REMARKS: 040900Z POSITION NEAR 12.5S 167.8E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 318 NM NORTH OF PORT VILA, VANUATU, HAS TRACKED WESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THE SYSTEM HAS CONTINUED TO DEEPEN AS SPIRAL BANDS CURVED TIGHTER INTO THE CENTER. THE INITIAL POSITION IS BASED ON A DIMPLE FEATURE IN THE MSI LOOP THAT LINES UP WELL WITH A LOW REFLECTIVITY CIRCULATION FEATURE IN THE 040442Z AMSU MICROWAVE PASS. THE INITIAL INTENSITY IS BASED ON AN OVERALL ASSESSMENT OF AGENCY AND OBJECTIVE DVORAK ESTIMATES RANGING FROM T4.5 TO T4.6 AND REFLECTS THE DEEPENED STATE OF THE CYCLONE. ENVIRONMENTAL ANALYSIS INDICATES A VERY FAVORABLE ENVIRONMENT WITH WARM SSTS NEAR 30 CELSIUS AND EXCELLENT RADIAL OUTFLOW ALOFT. THERE IS LIGHT TO MODERATE ALONG-TRACK VERTICAL WIND SHEAR (VWS) BUT IS MOSTLY OFFSET THE OUTFLOW AND THE STORM MOTION THAT IS IN-PHASE WITH THE UPPER LEVEL WIND FLOW. TC DONNA IS TRACKING ALONG THE NORTHERN PERIPHERY OF A BUILDING SUBTROPICAL RIDGE (STR) TO THE SOUTH. AFTER TAU 36, A MID-LATITUDE TROUGH APPROACHING FROM THE SOUTHWEST IS EXPECTED TO WEAKEN THE STR AND CAUSE THE CYCLONE TO TRACK POLEWARD THEN ACCELERATE SOUTHEASTWARD. AS FAVORABLE CONDITIONS PERSIST IN THE NEAR- TO MID-TERM, THE SYSTEM WILL CONTINUE TO INTENSIFY, PEAKING AT 110 KNOTS NEAR TAU 72. AFTERWARD, INCREASING VWS AND COOLING SSTS WILL GRADUALLY WEAKEN THE CYCLONE. NUMERICAL MODEL GUIDANCE SHOWS OVERALL IMPROVED AGREEMENT WITH GFDN AS THE SOLE WESTWARD OUTLIER. THE JTWC FORECAST TRACK IS PLACED WITH HIGH CONFIDENCE JUST EAST OF THE MULTI-MODEL CONSENSUS TO OFFSET GFDN. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 040600Z IS 24 FEET. NEXT WARNINGS AT 042100Z AND 050900Z.// ========================================================================= WTPS31 PGTW 20170504 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 005// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 005 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 041800Z --- NEAR 13.0S 166.8E MOVEMENT PAST SIX HOURS - 245 DEGREES AT 09 KTS POSITION ACCURATE TO WITHIN 025 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 13.0S 166.8E --- FORECASTS: 12 HRS, VALID AT: 050600Z --- 13.6S 165.8E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 240 DEG/ 04 KTS --- 24 HRS, VALID AT: 051800Z --- 14.0S 165.1E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 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 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 215 DEG/ 02 KTS --- 36 HRS, VALID AT: 060600Z --- 14.4S 164.8E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 180 DEG/ 03 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 061800Z --- 15.0S 164.8E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 160 DEG/ 05 KTS --- 72 HRS, VALID AT: 071800Z --- 16.9S 165.6E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 150 DEG/ 06 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 081800Z --- 19.1S 166.9E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 140 DEG/ 06 KTS --- 120 HRS, VALID AT: 091800Z --- 21.0S 168.6E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT --- REMARKS: 042100Z POSITION NEAR 13.2S 166.5E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 295 NM NORTH- NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED WEST-SOUTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP CENTRAL CONVECTION WITH A BROAD COLD OVERCAST LAYER. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON A FORMING LOW LEVEL EYE FEATURE OBSERVED IN A 041650Z 37 GHZ SSMIS IMAGE. THE INITIAL INTENSITY IS BASED ON AGENCY DVORAK ESTIMATES RANGING FROM 4.5 TO 5.0 (77 TO 90 KNOTS). ENVIRONMENTAL CONDITIONS ARE CURRENTLY FAVORABLE SUPPORTING FURTHER INTENSIFICATION WITH SSTS NEAR 30 CELSIUS AND NEAR-RADIAL OUTFLOW ALOFT. A POINT SOURCE ANALYZED JUST TO THE NORTH IS CREATING SOME WIND SHEAR ON THE NORTHERN PERIPHERY, HOWEVER THE SYSTEM IS TRACKING IN-PHASE WITH THE DIRECTION OF THE SHEAR. CURRENTLY TC DONNA IS TRACKING WEST-SOUTHWESTWARD GUIDED BY A SUBTROPICAL RIDGE TO THE SOUTH. A BREAK IN THE STEERING RIDGE IS EXPECTED IN THE NEXT 12 TO 24 HOURS SLOWING THE SYSTEM DOWN AS A RIDGE TO THE SOUTHWEST COMPETES WITH THE DOMINANT SOUTHEAST RIDGE. DURING THIS TIME FURTHER INTENSIFICATION IS EXPECTED AS A TROUGH MOVES IN FROM THE WEST ENHANCING OUTFLOW. TC DONNA WILL REACH PEAK INTENSITY OF 110 BY TAU 48. THE APPROACHING TROUGH WILL ERODE THE WESTERN RIDGE AND THE SYSTEM WILL TURN AND BEGIN TO ACCELERATE TO THE SOUTHEAST AROUND TAU 48. HIGH WINDS ALOFT WILL INTRODUCE VERTICAL WIND SHEAR AND BEGIN WEAKENING THE SYSTEM BY TAU 96. NUMERICAL MODEL GUIDANCE IS COMING INTO BETTER AGREEMENT WITH THE TRACK TRAJECTORY, BUT THERE IS STILL A LARGE DEGREE OF UNCERTAINTY AS TO WHEN AND WHERE TC DONNA WILL MAKE THE TURN TO THE SOUTHEAST. OVERALL, THE AVAILABLE GUIDANCE HAS SHIFTED TO THE WEST IN RECENT MODEL RUNS, AND THE JTWC FORECAST TRACK REFLECTS THIS CHANGE. DUE TO THE LARGE UNCERTAINTY THERE IS LOW CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 041800Z IS 28 FEET. NEXT WARNINGS AT 050300Z, 050900Z, 051500Z AND 052100Z.// ========================================================================= WTPS31 PGTW 20170505 03:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 006// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 006 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 050000Z --- NEAR 13.1S 166.2E MOVEMENT PAST SIX HOURS - 250 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 13.1S 166.2E --- FORECASTS: 12 HRS, VALID AT: 051200Z --- 13.6S 165.3E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 230 DEG/ 03 KTS --- 24 HRS, VALID AT: 060000Z --- 14.0S 164.8E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 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 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 190 DEG/ 03 KTS --- 36 HRS, VALID AT: 061200Z --- 14.5S 164.7E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 170 DEG/ 04 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 070000Z --- 15.2S 164.8E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 165 DEG/ 05 KTS --- 72 HRS, VALID AT: 080000Z --- 17.1S 165.3E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 145 DEG/ 06 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 090000Z --- 19.1S 166.8E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 135 DEG/ 06 KTS --- 120 HRS, VALID AT: 100000Z --- 20.7S 168.6E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT --- REMARKS: 050300Z POSITION NEAR 13.2S 166.0E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 302 NM NORTH- NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED WEST-SOUTHWESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS WEAKENING CONVECTION AND WARMING CLOUD TOPS. THE INITIAL POSITION IS EXTRAPOLATED FROM A LOW REFLECTIVITY FEATURE IN A 042215Z AMSU-B IMAGE WITH FAIR CONFIDENCE. THE INITIAL INTENSITY IS BASED ON BOTH OBJECTIVE AND AGENCY CURRENT INTENSITY DVORAK ESTIMATES RANGING FROM 4.5 TO 5.0 (77 TO 90 KNOTS). ENVIRONMENTAL CONDITIONS HAVE DETERIORATED IN THE UPPER-LEVELS OVER THE LAST SIX HOURS DUE TO A POINT SOURCE ANALYZED TO THE NORTHEAST WHICH IS RESTRICTING OUTFLOW ON THE NORTH AND EASTERN QUADRANTS AND CREATING A MODERATE SHEAR ENVIRONMENT. STRONG POLEWARD DIFFLUENCE IS STILL EVIDENT IN SATELLITE IMAGERY TAPPING INTO THE MID-LATITUDE JET. SSTS ARE ALSO VERY WARM IN THE REGION, NEAR 30 CELSIUS. CURRENTLY TC DONNA IS TRACKING WEST-SOUTHWESTWARD GUIDED BY A SUBTROPICAL RIDGE TO THE SOUTH. A BREAK IN THE STEERING RIDGE IS EXPECTED IN THE NEXT 12 TO 24 HOURS SLOWING THE SYSTEM DOWN AS A RIDGE TO THE SOUTHWEST COMPETES WITH THE DOMINANT SOUTHEAST RIDGE. OVER THE NEXT 24 HOURS MODERATE SHEAR DUE TO NORTHEASTERLY FLOW ALOFT IS EXPECTED TO PERSIST AND WILL MITIGATE DEVELOPMENT. BEYOND TAU 24 A LONGWAVE TROUGH WILL MOVE INTO THE REGION ENHANCING OUTFLOW, AND PRIME TC DONNA FOR ANOTHER PERIOD OF INTENSIFICATION. PEAK INTENSITY IS EXPECTED TO REACH 110 BY TAU 48. THE APPROACHING TROUGH WILL ALSO ERODE THE WESTERN RIDGE AND THE SYSTEM WILL TURN AND BEGIN TO ACCELERATE TO THE SOUTHEAST AROUND TAU 48. HIGH WINDS ALOFT ASSOCIATED WITH THE TROUGH WILL INTRODUCE SIGNIFICANT VERTICAL WIND SHEAR AND BEGIN WEAKENING THE SYSTEM AFTER TAU 72. NUMERICAL MODEL GUIDANCE IS COMING INTO BETTER AGREEMENT WITH THE TRACK TRAJECTORY, HOWEVER THERE IS STILL A LARGE DEGREE OF UNCERTAINTY IN THE EXACT POSITION AND TIMING TC DONNA WILL MAKE THE TURN TO THE SOUTHEAST. OVERALL, THE AVAILABLE GUIDANCE HAS SHIFTED THE TRACK TO THE WEST IN RECENT MODEL RUNS, AND THIS TREND IS BEGINNING TO STABILIZE, THUS IMPROVING CONFIDENCE IN THE FORECAST TRACK. DUE TO THE INHERENT UNCERTAINTY IN THE SOUTHWARD TURN, THERE IS OVERALL LOW CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 041800Z IS 28 FEET. NEXT WARNINGS AT 050300Z, 050900Z, 051500Z AND 052100Z.// ========================================================================= WTPS31 PGTW 20170505 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 007// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 007 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 050600Z --- NEAR 13.6S 165.6E MOVEMENT PAST SIX HOURS - 230 DEGREES AT 08 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 - 025 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 13.6S 165.6E --- FORECASTS: 12 HRS, VALID AT: 051800Z --- 14.0S 164.9E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 215 DEG/ 02 KTS --- 24 HRS, VALID AT: 060600Z --- 14.4S 164.6E 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 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 190 DEG/ 03 KTS --- 36 HRS, VALID AT: 061800Z --- 14.9S 164.5E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 180 DEG/ 04 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 070600Z --- 15.7S 164.5E MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 165 DEG/ 06 KTS --- 72 HRS, VALID AT: 080600Z --- 17.9S 165.1E MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 145 DEG/ 06 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 090600Z --- 19.9S 166.7E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 130 DEG/ 07 KTS --- 120 HRS, VALID AT: 100600Z --- 21.7S 169.0E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT --- REMARKS: 050900Z POSITION NEAR 13.7S 165.4E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 291 NM NORTH-NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWESTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THE SYSTEM HAS CONTINUED TO DEEPEN AS SPIRAL BANDS CURVED TIGHTER INTO THE CENTER. THE INITIAL POSITION IS BASED ON A DIMPLE FEATURE IN THE MSI LOOP THAT LINES UP WELL WITH A LOW REFLECTIVITY CIRCULATION FEATURE IN THE 050409Z SSMI MICROWAVE PASS. THE INITIAL INTENSITY IS BASED ON AN OVERALL ASSESSMENT OF AGENCY AND OBJECTIVE DVORAK ESTIMATES AND REFLECTS THE DEEPENED STATE OF THE CYCLONE. ENVIRONMENTAL ANALYSIS INDICATES A VERY FAVORABLE ENVIRONMENT WITH WARM SSTS NEAR 30 CELSIUS AND EXCELLENT RADIAL OUTFLOW ALOFT. THERE IS LIGHT TO MODERATE ALONG-TRACK VERTICAL WIND SHEAR (VWS) BUT IS MOSTLY OFFSET BY THE OUTFLOW AND THE STORM MOTION THAT IS IN-PHASE WITH THE UPPER LEVEL WIND FLOW. TC DONNA IS TRACKING ALONG THE NORTHWESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) TO THE SOUTH. AFTER TAU 24, A MID-LATITUDE TROUGH APPROACHING FROM THE SOUTHWEST IS EXPECTED TO WEAKEN THE STR AND CAUSE THE CYCLONE TO TRACK POLEWARD THEN ACCELERATE SOUTHEASTWARD. AS FAVORABLE CONDITIONS PERSIST IN THE NEAR- TO MID-TERM, THE SYSTEM WILL CONTINUE TO INTENSIFY, PEAKING AT 115 KNOTS BETWEEN TAU 36-48. AFTERWARD, INCREASING VWS AND COOLING SSTS WILL GRADUALLY WEAKEN THE CYCLONE. BY TAU 120, TC DONNA WILL BEGIN EXTRA-TROPICAL TRANSITION. NUMERICAL MODEL GUIDANCE IS IN OVERALL AGREEMENT WITH EGRR AS THE SOLE EASTWARD OUTLIER. THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 050600Z IS 30 FEET. NEXT WARNINGS AT 052100Z AND 060900Z.// ========================================================================= WTPS31 PGTW 20170505 15:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 008// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 008 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 051200Z --- NEAR 13.8S 165.0E MOVEMENT PAST SIX HOURS - 240 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 015 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 - 025 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 13.8S 165.0E --- FORECASTS: 12 HRS, VALID AT: 060000Z --- 14.2S 164.4E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 215 DEG/ 02 KTS --- 24 HRS, VALID AT: 061200Z --- 14.5S 164.2E 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 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 190 DEG/ 03 KTS --- 36 HRS, VALID AT: 070000Z --- 15.0S 164.1E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 175 DEG/ 06 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 071200Z --- 16.2S 164.2E MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 160 DEG/ 06 KTS --- 72 HRS, VALID AT: 081200Z --- 18.3S 164.9E MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 140 DEG/ 07 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 091200Z --- 20.3S 166.8E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 130 DEG/ 08 KTS --- 120 HRS, VALID AT: 101200Z --- 22.2S 169.3E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT --- REMARKS: 051500Z POSITION NEAR 13.9S 164.8E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 302 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED WEST-SOUTHWESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY (EIR) SHOWS THE SYSTEM HAS MAINTAINED A DEEP CENTRAL DENSE OVERCAST FEATURE WITH TIGHT SPIRAL BANDS THE INITIAL POSITION IS BASED ON A WARM PIXEL IN THE EIR THAT LINES UP WELL WITH A LOW REFLECTIVITY CIRCULATION FEATURE IN THE 051048Z AMSU MICROWAVE PASS. THE INITIAL INTENSITY IS BASED ON AN OVERALL ASSESSMENT OF AGENCY AND OBJECTIVE DVORAK ESTIMATES ENVIRONMENTAL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH WARM SSTS NEAR 30 CELSIUS AND EXCELLENT POLEWARD OUTFLOW. THERE IS LIGHT TO MODERATE ALONG-TRACK VERTICAL WIND SHEAR (VWS) BUT IS MOSTLY OFFSET BY THE OUTFLOW AND THE STORM MOTION THAT IS IN-PHASE WITH THE UPPER LEVEL WIND FLOW. TC DONNA IS TRACKING ALONG THE NORTHWESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) TO THE SOUTH. AFTER TAU 12, A MID-LATITUDE TROUGH APPROACHING FROM THE SOUTHWEST IS EXPECTED TO WEAKEN THE STR AND CAUSE THE CYCLONE TO TRACK POLEWARD THEN ACCELERATE SOUTHEASTWARD. AS FAVORABLE CONDITIONS PERSIST IN THE NEAR- TO MID-TERM, THE SYSTEM WILL CONTINUE TO INTENSIFY, PEAKING AT 115 KNOTS BETWEEN TAU 48-72. AFTERWARD, INCREASING VWS AND COOLING SSTS WILL GRADUALLY WEAKEN THE CYCLONE. BY TAU 120, TC DONNA WILL BEGIN EXTRA-TROPICAL TRANSITION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 051200Z IS 30 FEET. NEXT WARNINGS AT 060300Z AND 061500Z.// ========================================================================= WTPS31 PGTW 20170505 21:00z 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.// ========================================================================= WTPS31 PGTW 20170506 03:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 010// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 010 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 060000Z --- NEAR 13.1S 163.9E MOVEMENT PAST SIX HOURS - 315 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 190 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT REPEAT POSIT: 13.1S 163.9E --- FORECASTS: 12 HRS, VALID AT: 061200Z --- 13.0S 163.5E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 175 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 190 DEG/ 05 KTS --- 24 HRS, VALID AT: 070000Z --- 14.0S 163.3E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 185 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 135 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 175 DEG/ 07 KTS --- 36 HRS, VALID AT: 071200Z --- 15.3S 163.4E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 185 NM NORTHEAST QUADRANT 205 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 135 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 155 DEG/ 07 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 080000Z --- 16.5S 164.0E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 145 DEG/ 07 KTS --- 72 HRS, VALID AT: 090000Z --- 18.8S 165.7E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 135 DEG/ 10 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 100000Z --- 21.6S 168.7E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 135 DEG/ 11 KTS --- 120 HRS, VALID AT: 110000Z --- 24.6S 171.9E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 235 NM NORTHEAST QUADRANT 260 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT --- REMARKS: 060300Z POSITION NEAR 13.1S 163.8E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 375 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED NORTHWESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) REVEALS A SIGNIFICANTLY WEAKENED CONVECTIVE SIGNATURE, WITH THE PREVIOUSLY ESTABLISHED CENTRAL COLD COVER (CCC) HAVING COMPLETELY DISSIPATED, WITH ONLY PATCHY MODERATE CONVECTION. AS OF THE LATE 0000Z HOUR, SIGNS OF REDEVELOPMENT OF DEEP CONVECTION HAVE APPEARED, BUT IT IS TOO EARLY TO DETERMINE IF THIS WILL STICK. THE INITIAL POSITION IS PLACED WITH MODERATE CONFIDENCE BASED ON ANALYSIS OF THE AVAILABLE HIGH RESOLUTION VISIBLE IMAGERY AND A 2156Z AMSU 89 GHZ MICROWAVE IMAGE AND COINCIDENT ASCAT-B PASS, WITH A WELL DEFINED LOW LEVEL CIRCULATION CENTER (LLCC), STILL SHIELDED FROM VIEW BY UPPER-LEVEL CLOUD COVER. THE INITIAL INTENSITY OF 85 KNOTS IS BASED ON ASSESSMENT OF REPORTING AGENCY AND AUTOMATED DVORAK CURRENT INTENSITY ESTIMATES BETWEEN 4.5 AND 5.0 AND SUPPORTED BY THE OVERALL WEAKENED APPEARANCE OF THE SYSTEM. BASED ON ANALYSIS OF THE UPPER- LEVEL DATA, THE RECENT WEAKENING PHASE WILL BE SHORT LIVED, AND WAS DRIVEN BY AN INCREASED NORTHEASTERLY UPPER-LEVEL FLOW OVER TOP OF THE SYSTEM. RECENT ANALYSIS INDICATES A SHIFT FROM THIS NORTHEASTERLY FLOW PATTERN TO DEVELOPMENT OF AN UPPER-LEVEL POINT SOURCE IN THE NEAR TERM. THE OVERALL ENVIRONMENT REMAINS SUPPORTIVE OF INTENSIFICATION WITH WARM SSTS NEAR 29 CELSIUS, A STRONG POLEWARD OUTFLOW CHANNEL AND LOW TO MODERATE VERTICAL WIND SHEAR (VWS) VALUES BETWEEN 15-20 KNOTS. OVER THE PAST SIX HOURS, TC DONNA HAS CONTINUED TO TRACK WEST-NORTHWESTWARD UNDER THE INFLUENCE OF AN ELONGATED SUBTROPICAL RIDGE (STR) AXIS ALONG TONGA TO NEW CALEDONIA TO NORTHEAST AUSTRALIA AXIS, WHICH CONTINUES TO INHIBIT SOUTHWARD MOVEMENT AT THIS TIME. THIS RIDGE IS EXPECTED TO BREAK DOWN AND REORIENT TO A MORE NORTH-SOUTH AXIS BY TAU 24, ALLOWING TC DONNA TO TURN POLEWARD AND ACCELERATE THROUGH THE REMAINDER OF THE FORECAST. AS THE AFOREMENTIONED POINT SOURCE DEVELOPS OVER TOP OF THE SYSTEM, ENVIRONMENTAL CONDITIONS WILL BE RIPE FOR FURTHER INTENSIFICATION THROUGH TAU 48, PEAKING AT 110 KNOTS BEFORE BEGINNING A WEAKENING TREND AFTER TAU 72 AS VWS INCREASES AND SSTS DECREASE. TC DONNA WILL BEGIN TO UNDERGO EXTRATROPICAL TRANSITION BY TAU 96 THROUGH THE REMAINDER OF THE FORECAST. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT WITH EGRR REMAINING AS THE SOLE EASTWARD OUTLIER, LEADING TO TO HIGH CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 050600Z IS 30 FEET. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 060000Z IS 30 FEET. NEXT WARNINGS AT 060900Z, 061500Z, 062100Z AND 070300Z.// ========================================================================= WTPS31 PGTW 20170506 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 011 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 060600Z --- NEAR 13.4S 164.1E MOVEMENT PAST SIX HOURS - 225 DEGREES AT 03 KTS POSITION ACCURATE TO WITHIN 035 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 190 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT REPEAT POSIT: 13.4S 164.1E --- FORECASTS: 12 HRS, VALID AT: 061800Z --- 13.8S 163.8E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 190 DEG/ 06 KTS --- 24 HRS, VALID AT: 070600Z --- 15.0S 163.6E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 135 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 170 DEG/ 07 KTS --- 36 HRS, VALID AT: 071800Z --- 16.3S 163.8E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 185 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 160 DEG/ 07 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 080600Z --- 17.7S 164.3E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 150 DEG/ 07 KTS --- 72 HRS, VALID AT: 090600Z --- 20.1S 165.9E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 140 DEG/ 10 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 100600Z --- 23.3S 168.7E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 165 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 130 DEG/ 16 KTS --- 120 HRS, VALID AT: 110600Z --- 27.0S 174.2E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 250 NM NORTHEAST QUADRANT 245 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT --- REMARKS: 060900Z POSITION NEAR 13.5S 164.0E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 354 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWESTWARD AT 03 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS AN OVERALL WEAKENING TREND DESPITE A RECENT RESURGENCE OF DEEP CONVECTION AND CURVED BANDING. A 060514Z SSMIS 37 GHZ IMAGE INDICATES AN ORGANIZED LOW-LEVEL CIRCULATION CENTER WITH SHALLOW BANDING WRAPPING INTO A WELL-DEFINED MICROWAVE EYE FEATURE, WHICH SUPPORTS THE CURRENT POSITION WITH GOOD CONFIDENCE BUT EVIDENCES A QUASI-STATIONARY TRACK MOTION. THE CURRENT INTENSITY IS ASSESSED AT 80 KNOTS BASED ON AN AVERAGE OF DVORAK ESTIMATES RANGING FROM 4.0 TO 5.0 REFLECTING THE OVERALL WEAKENING TREND. TC 18P IS CURRENTLY LOCATED WITHIN A COMPETING STEERING ENVIRONMENT BETWEEN A WEAK SUBTROPICAL RIDGE (STR) OVER NORTHEAST AUSTRALIA AND A STRONG STR TO THE EAST. THE WESTERN STR IS FORECAST TO WEAKEN SIGNIFICANTLY AS A DEEP MIDLATITUDE TROUGH DEEPENS ACROSS THE CORAL SEA, WHICH WILL ALLOW THE EASTERN STR TO BECOME THE DOMINANT STEERING INFLUENCE WITHIN THE NEXT 24 TO 36 HOURS. TC DONNA IS FORECAST TO INTENSIFY TO A PEAK OF 110 KNOTS UNDER FAVORABLE CONDITIONS TO INCLUDE WARM SST, LOW VERTICAL WIND SHEAR (VWS) AND ROBUST POLEWARD OUTFLOW. AFTER TAU 36, TC 18P SHOULD BEGIN TO ACCELERATE SOUTHWARD AS IT TRACKS ALONG THE WESTERN PERIPHERY OF THE STR. GRADUAL WEAKENING SHOULD OCCUR AS THE SYSTEM TRACKS OVER COOLER SST. NEAR TAU 72, TC 18P WILL BEGIN EXTRA-TROPICAL TRANSITION AS IT INTERACTS WITH THE MIDLATITUDE WESTERLIES AND A WEAK BAROCLINIC ZONE. THE SYSTEM WILL ACCELERATE SOUTHEASTWARD AFTER TAU 72 AS IT COMPLETES EXTRA-TROPICAL TRANSITION AND BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST. DURING THE EXTENDED PERIOD, TC 18P WILL WEAKEN RAPIDLY DUE TO INCREASING VWS AND COOL SST UNDER 26C. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 060600Z IS 30 FEET. NEXT WARNINGS AT 061500Z, 062100Z, 070300Z AND 070900Z.// ========================================================================= WTPS31 PGTW 20170506 15:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 012 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 061200Z --- NEAR 13.5S 164.1E MOVEMENT PAST SIX HOURS - 205 DEGREES AT 02 KTS POSITION ACCURATE TO WITHIN 025 NM POSITION BASED ON EYE FIXED 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 - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 190 NM SOUTHWEST QUADRANT 145 NM NORTHWEST QUADRANT REPEAT POSIT: 13.5S 164.1E --- FORECASTS: 12 HRS, VALID AT: 070000Z --- 14.2S 163.9E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 180 DEG/ 06 KTS --- 24 HRS, VALID AT: 071200Z --- 15.4S 163.9E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 135 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 170 DEG/ 07 KTS --- 36 HRS, VALID AT: 080000Z --- 16.8S 164.2E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 185 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 160 DEG/ 07 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 081200Z --- 18.2S 164.7E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 145 DEG/ 08 KTS --- 72 HRS, VALID AT: 091200Z --- 20.9S 166.6E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 135 DEG/ 12 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 101200Z --- 24.1S 170.2E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 165 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 130 DEG/ 15 KTS --- 120 HRS, VALID AT: 111200Z --- 27.7S 175.6E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 250 NM NORTHEAST QUADRANT 245 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT --- REMARKS: 061500Z POSITION NEAR 13.7S 164.0E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 350 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTH-SOUTHWESTWARD AT 02 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A RAGGED 12-NM EYE WITH IMPROVED CONVECTIVE STRUCTURE. HOWEVER, THE MOST RECENT EIR IMAGERY INDICATES THAT THE EYE HAS FILLED. A 061113Z METOP-A 89 GHZ IMAGE SHOWS THE BULK OF DEEP CONVECTION IS CONFINED TO THE NORTHERN SEMI-CIRCLE WITH AN ASYMMETRIC MICROWAVE EYE FEATURE POSITIONED ALONG THE SOUTHERN EDGE OF THIS DEEP CONVECTION. BASED ON THE EYE AND RECENT MICROWAVE IMAGERY, THERE IS GOOD CONFIDENCE IN THE CURRENT POSITION. TRACK MOTION REMAINS SLOW WITH A SLIGHT SOUTHWARD DRIFT. THE CURRENT INTENSITY IS ASSESSED AT 90 KNOTS BASED ON DVORAK ESTIMATES OF T5.0 FROM PGTW, PHFO AND KNES. TC 18P IS CURRENTLY LOCATED WITHIN A COMPETING STEERING ENVIRONMENT BETWEEN A WEAK SUBTROPICAL RIDGE (STR) OVER NORTHEAST AUSTRALIA AND A STRONG STR TO THE EAST. THE WESTERN STR IS FORECAST TO WEAKEN SIGNIFICANTLY AS A DEEP MIDLATITUDE TROUGH DEEPENS ACROSS THE CORAL SEA, WHICH WILL ALLOW THE EASTERN STR TO BECOME THE DOMINANT STEERING INFLUENCE WITHIN THE NEXT 24 TO 36 HOURS. TC DONNA IS FORECAST TO INTENSIFY TO A PEAK OF 110 KNOTS UNDER FAVORABLE CONDITIONS TO INCLUDE WARM SST, LOW VERTICAL WIND SHEAR (VWS) AND ROBUST POLEWARD OUTFLOW. AFTER TAU 36, TC 18P SHOULD BEGIN TO ACCELERATE SOUTHWARD AS IT TRACKS ALONG THE WESTERN PERIPHERY OF THE STR. GRADUAL WEAKENING SHOULD OCCUR AS THE SYSTEM TRACKS OVER COOLER SST. NEAR TAU 72, TC 18P WILL BEGIN EXTRA-TROPICAL TRANSITION AS IT INTERACTS WITH THE MIDLATITUDE WESTERLIES AND A WEAK BAROCLINIC ZONE. THE SYSTEM WILL ACCELERATE SOUTHEASTWARD AFTER TAU 72 AS IT COMPLETES EXTRA-TROPICAL TRANSITION AND BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST. DURING THE EXTENDED PERIOD, TC 18P WILL WEAKEN RAPIDLY DUE TO INCREASING VWS AND COOL SST LESS THAN 25C. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 061200Z IS 30 FEET. NEXT WARNINGS AT 062100Z, 070300Z, 070900Z AND 071500Z.// ========================================================================= WTPS31 PGTW 20170506 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 013// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 013 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 061800Z --- NEAR 13.4S 164.1E MOVEMENT PAST SIX HOURS - 180 DEGREES AT 02 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 - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 165 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT REPEAT POSIT: 13.4S 164.1E --- FORECASTS: 12 HRS, VALID AT: 070600Z --- 14.3S 164.1E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 060 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 165 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 170 DEG/ 06 KTS --- 24 HRS, VALID AT: 071800Z --- 15.5S 164.3E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 060 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 185 NM NORTHEAST QUADRANT 205 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 170 DEG/ 07 KTS --- 36 HRS, VALID AT: 080600Z --- 16.9S 164.6E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT 205 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 155 DEG/ 09 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 081800Z --- 18.5S 165.4E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 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 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 145 DEG/ 09 KTS --- 72 HRS, VALID AT: 091800Z --- 21.2S 167.6E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 005 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 005 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 135 DEG/ 11 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 101800Z --- 24.1S 170.9E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT --- REMARKS: 062100Z POSITION NEAR 13.6S 164.1E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 354 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWARD AT 02 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY INDICATES 18P IS ENTERING ANOTHER RELATIVE CONVECTIVE LULL IN ITS CONTINUED PATTERN OF PULSATING DEEP CONVECTION OBSERVED OVER THE PAST SEVERAL DAYS. BANDING REMAINS TIGHTLY WRAPPED INTO AN ILL-DEFINED LOW LEVEL CIRCULATION CENTER, AND A LARGE CONVECTIVE ASYMMETRY HAS FORMED TO THE SOUTHEAST. A 061624Z SSMIS 91 GHZ IMAGE REVEALS THE INTENSE CONVECTION ASSOCIATED WITH THE CENTRAL BANDING, AND THE 37 GHZ CHANNEL PRESENTS A WELL DEFINED MICROWAVE EYE. THE INITIAL POSITION IS EXTRAPOLATED FROM THE AFOREMENTIONED MICROWAVE EYE. A RE-ANALYSIS OF RECENT MICROWAVE IMAGERY, INCLUDING A 061114Z BYU ASCAT PRODUCT AND ASSOCIATED NORMALIZED RADAR CROSS SECTION INDICATES DONNA HAS REMAINED ALMOST QUASI-STATIONARY (QS) FOR NEARLY 18 HOURS. THE CURRENT INTENSITY IS ASSESSED AT 90 KNOTS BASED ON DVORAK ESTIMATES OF T5.0 FROM PGTW AND KNES. TC 18P IS CURRENTLY LOCATED WITHIN A COMPETING STEERING ENVIRONMENT BETWEEN A WEAK SUBTROPICAL RIDGE (STR) OVER NORTHEAST AUSTRALIA AND A STRONG STR TO THE EAST. GLOBAL MODEL ANALYSES ARE STARTING TO SUGGEST THE WESTERN STR IS FINALLY STARTING TO ERODE, WITH THE EASTERN STR EXPECTED TO BECOME THE DOMINANT STEERING INFLUENCE OVER THE NEXT DAY RESULTING IN A MORE PRONOUNCED SOUTHWARD MOTION. UPWELLING DURING THIS QS PERIOD HAS LIKELY TEMPERED THE POTENTIAL FOR INTENSIFICATION. ADDITIONALLY, ALTHOUGH VERTICAL WIND SHEAR (VWS) IS RELATIVELY LIGHT, THE BROAD AND DIFFUSE UPPER LEVEL WINDS OVER THE CENTER HAVE NEGATIVELY IMPACTED THE ORGANIZATION OF THE CENTRAL CORE. AS TC DONNA BEGINS TO MOVE TO THE SOUTH OVER WARMER WATERS, CONTINUED ROBUST OUTFLOW MAY ALLOW SOME ADDITIONAL INTENSIFICATION, WITH THE UPPER END OF THE GUIDANCE AROUND 105 KNOTS. THE SYSTEM WILL ACCELERATE AND TURN SOUTHEASTWARD AROUND TAU 48. EXTRA-TROPICAL TRANSITION WILL BEGIN AROUND TAU 72 AS TC DONNA MOVES OVER COOLER WATERS AND BEGINS TO INTERACT WITH THE BAROCLINIC ZONE. A SIGNIFICANT INCREASE IN VWS AT THAT TIME WILL INITIATE RAPID WEAKENING. DONNA IS EXPECTED TO COMPLETE EXTRA-TROPICAL TRANSITION AND BE FULLY EMBEDDED WITHIN THE MID-LATITUDE WESTERLIES BY TAU 96. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 061800Z IS 27 FEET. NEXT WARNINGS AT 070300Z, 070900Z, 071500Z, AND 072100Z. ========================================================================= WTPS31 PGTW 20170507 03:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 014// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 014 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 070000Z --- NEAR 13.8S 164.1E MOVEMENT PAST SIX HOURS - 180 DEGREES AT 04 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT REPEAT POSIT: 13.8S 164.1E --- FORECASTS: 12 HRS, VALID AT: 071200Z --- 14.9S 164.2E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 175 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 170 DEG/ 07 KTS --- 24 HRS, VALID AT: 080000Z --- 16.3S 164.4E MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 215 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 160 DEG/ 08 KTS --- 36 HRS, VALID AT: 081200Z --- 17.9S 165.0E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 210 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 150 DEG/ 08 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 090000Z --- 19.2S 165.8E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 145 DEG/ 10 KTS --- 72 HRS, VALID AT: 100000Z --- 22.4S 168.2E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 135 DEG/ 12 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 110000Z --- 25.5S 172.0E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 215 NM NORTHEAST QUADRANT 220 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT --- REMARKS: 070300Z POSITION NEAR 14.1S 164.1E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 337 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) INDICATES A RAGGED EYE IS TRYING TO FORM AS SPIRAL BANDING WRAPS INTO A LOW LEVEL CIRCULATION CENTER (LLCC), HOWEVER, CLOUD TOPS HAVE BEEN WARMING. A 062220Z AMSU 89 GHZ IMAGE REVEALS THE PRIMARY SPIRAL BAND IS WRAPPING AROUND A 50 NM DIAMETER MICROWAVE EYE. THE INITIAL POSITION IS EXTRAPOLATED FROM THE AFOREMENTIONED MICROWAVE EYE AND THE PGTW FIX. THE CURRENT INTENSITY WAS REDUCED SLIGHTLY TO 85 KNOTS BASED ON A RANGE OF DVORAK ESTIMATES FROM T4.5-5.0 (77 TO 90 KNOTS) FROM PGTW AND KNES, RELECTING THE SLIGHTLY WEAKENED CONVECTION. TC 18P IS CURRENTLY LOCATED WITHIN A COMPETING STEERING ENVIRONMENT BETWEEN A WEAK SUBTROPICAL RIDGE (STR) OVER NORTHEAST AUSTRALIA AND A STRONG STR TO THE EAST. GLOBAL MODEL ANALYSES SUGGEST THE EASTERN STR SHOULD BECOME THE DOMINANT STEERING INFLUENCE OVER THE NEXT DAY, RESULTING IN A MORE PRONOUCED SOUTHWARD MOTION. UPWELLING HAS LIKELY TEMPERED THE POTENTIAL FOR INTENSIFICATION DUE TO VERY SLOW MOTION OVER THE PAST 24 HOURS. VERTICAL WIND SHEAR (VWS) IS RELATIVELY LIGHT, HOWEVER, THE BROAD AND DIFFUSE UPPER LEVEL WINDS OVER THE CENTER HAVE HAMPERED THE ORGANIZATION OF THE CENTRAL CORE. AS TC DONNA BEGINS TO MOVE TO THE SOUTH OVER WARMER WATERS, CONTINUED ROBUST OUTFLOW MAY ALLOW SOME ADDITIONAL INTENSIFICATION OVER THE NEXT 24 HOURS, WITH THE UPPER END OF THE GUIDANCE AROUND 105 KNOTS. THE SYSTEM WILL ACCELERATE AND TURN SOUTHEASTWARD AROUND TAU 36. EXTRA- TROPICAL TRANSITION WILL BEGIN NEAR TAU 48 AS TC DONNA MOVES OVER COOLER WATERS AND BEGINS TO INTERACT WITH THE BAROCLINIC ZONE. A SIGNIFICANT INCREASE IN VWS AT TAU 72 WILL INITIATE RAPID WEAKENING. DONNA IS EXPECTED TO COMPLETE EXTRA-TROPICAL TRANSITION AND BE FULLY EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES BY TAU 96. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 070000Z IS 24 FEET. NEXT WARNINGS AT 070900Z, 071500Z, 072100Z AND 080300Z. ========================================================================= WTPS31 PGTW 20170507 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 015// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 015 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 070600Z --- NEAR 14.6S 164.6E MOVEMENT PAST SIX HOURS - 150 DEGREES AT 08 KTS POSITION ACCURATE TO WITHIN 015 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT REPEAT POSIT: 14.6S 164.6E --- FORECASTS: 12 HRS, VALID AT: 071800Z --- 16.3S 164.9E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 175 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 165 DEG/ 08 KTS --- 24 HRS, VALID AT: 080600Z --- 17.8S 165.3E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 215 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 160 DEG/ 09 KTS --- 36 HRS, VALID AT: 081800Z --- 19.4S 166.0E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 210 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 145 DEG/ 10 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 090600Z --- 21.1S 167.2E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 12 KTS --- 72 HRS, VALID AT: 100600Z --- 24.7S 170.4E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT --- REMARKS: 070900Z POSITION NEAR 15.0S 164.7E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 283 NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTH-SOUTHEASTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS IMPROVED CONVECTIVE ORGANIZATION WITH A 17- NM EYE EVIDENT, HOWEVER, DEEP CONVECTION CONTINUES TO CYCLE RAPIDLY. A 070500Z SSMIS 91 GHZ IMAGE SHOWS ASYMMETRIC CORE CONVECTION WITH A DEEP CONVECTIVE BAND OVER THE WESTERN SEMI-CIRCLE AND SHALLOW BANDING OVER THE EASTERN SEMI-CIRCLE OF THE EYEWALL. UPPER-LEVEL ANALYSIS INDICATES CYCLONIC FLOW OVER THE CORE, WHICH IS LIKELY CONTRIBUTING TO THE FLAT TREND AND PULSATING CONVECTION, DIVERGING INTO A STRONG POLEWARD OUTFLOW CHANNEL TO THE SOUTHWEST. THE CURRENT INTENSITY REMAINS ASSESSED AT 85 KNOTS BASED ON AN AVERAGE OF 4.5/5.0 DVORAK ESTIMATES FROM PGTW, KNES AND PHFO. CURRENT MODEL ANALYSES INDICATE THAT THE WESTERN SUBTROPICAL RIDGE (STR) HAS ERODED DUE TO AN APPROACHING MAJOR SHORTWAVE TROUGH, THEREFORE, THE EASTERN STR IS NOW THE DOMINANT STEERING RIDGE. CONSEQUENTLY, TC 18P HAS ACCELERATED SOUTHWARD AS IT TRACKS ALONG THE WESTERN PERIPHERY OF THE STR. TC DONNA SHOULD CONTINUE TO TRACK SOUTHWARD TO SOUTH- SOUTHEASTWARD THROUGH THE FORECAST PERIOD. DYNAMIC GUIDANCE REMAINS IN TIGHT AGREEMENT LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. TC 18P IS FORECAST TO INTENSIFY SLIGHTLY WITHIN THE NEXT 24 HOURS DUE TO WARM SST AND ROBUST POLEWARD OUTFLOW WITH SOME UNCERTAINTY DUE TO THE COMPLEX UPPER-LEVEL FLOW OVER THE CORE. AFTER TAU 24, GRADUAL WEAKENING SHOULD OCCUR AS THE SYSTEM TRACKS OVER MARGINAL SST. BY TAU 48, TC 18P WILL BEGIN EXTRA-TROPICAL TRANSITION AND RAPIDLY WEAKEN AS IT INTERACTS WITH THE MIDLATITUDE WESTERLIES AND THE WEAK BAROCLINIC ZONE. THE SYSTEM IS EXPECTED TO COMPLETE EXTRA-TROPICAL TRANSITION AS IT BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 070600Z IS 24 FEET. NEXT WARNINGS AT 071500Z, 072100Z, 080300Z AND 080900Z.// ========================================================================= WTPS31 PGTW 20170507 15:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 016// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 016 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 071200Z --- NEAR 15.5S 164.8E MOVEMENT PAST SIX HOURS - 170 DEGREES AT 09 KTS POSITION ACCURATE TO WITHIN 020 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT REPEAT POSIT: 15.5S 164.8E --- FORECASTS: 12 HRS, VALID AT: 080000Z --- 17.1S 165.0E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 215 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 165 DEG/ 08 KTS --- 24 HRS, VALID AT: 081200Z --- 18.7S 165.5E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 205 NM SOUTHEAST QUADRANT 155 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 150 DEG/ 10 KTS --- 36 HRS, VALID AT: 090000Z --- 20.4S 166.5E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 145 DEG/ 11 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 091200Z --- 22.2S 167.8E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 12 KTS --- 72 HRS, VALID AT: 101200Z --- 25.6S 171.2E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT --- REMARKS: 071500Z POSITION NEAR 15.9S 164.8E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 241 NM WEST- NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS STRENGTHENING, ASYMMETRIC EYEWALL CONVECTION SURROUNDING A 21-NM EYE. A 071052Z METOP-A 89 GHZ IMAGE SHOWS DEEP CONVECTION PRIMARILY OVER THE WESTERN SEMI-CIRCLE AND SHALLOW CONVECTION OVER THE EASTERN SEMI-CIRCLE. UPPER-LEVEL ANALYSIS INDICATES CYCLONIC FLOW OVER THE SYSTEM, WHICH IS LIKELY CONTRIBUTING TO THE PULSATING, ASYMMETRIC CORE CONVECTION, DIVERGING INTO A STRONG POLEWARD OUTFLOW CHANNEL TO THE SOUTHWEST. THE CURRENT INTENSITY IS ASSESSED AT 95 KNOTS BASED ON AN AVERAGE OF DVORAK ESTIMATES RANGING FROM T5.0 TO T5.5. CURRENT MODEL ANALYSES INDICATE THAT THE WESTERN SUBTROPICAL RIDGE (STR) HAS ERODED DUE TO AN APPROACHING MAJOR SHORTWAVE TROUGH, THEREFORE, THE EASTERN STR IS NOW THE DOMINANT STEERING RIDGE. CONSEQUENTLY, TC 18P HAS ACCELERATED SOUTHWARD AS IT TRACKS ALONG THE WESTERN PERIPHERY OF THE DOMINANT STR. TC DONNA SHOULD CONTINUE TO TRACK SOUTHWARD TO SOUTH-SOUTHEASTWARD THROUGH THE FORECAST PERIOD. DYNAMIC GUIDANCE REMAINS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. TC 18P IS FORECAST TO INTENSIFY SLIGHTLY WITHIN THE NEXT 12 HOURS DUE TO WARM SST AND ROBUST POLEWARD OUTFLOW WITH SOME UNCERTAINTY DUE TO THE COMPLEX UPPER-LEVEL FLOW OVER THE CORE. AFTER TAU 12, GRADUAL WEAKENING SHOULD OCCUR AS THE SYSTEM TRACKS OVER MARGINAL SST. BY TAU 36, TC 18P WILL BEGIN EXTRA-TROPICAL TRANSITION AND RAPIDLY WEAKEN AS IT INTERACTS WITH THE MIDLATITUDE WESTERLIES AND THE WEAK BAROCLINIC ZONE. THE SYSTEM IS EXPECTED TO COMPLETE EXTRA-TROPICAL TRANSITION AS IT BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 071200Z IS 27 FEET. NEXT WARNINGS AT 072100Z, 080300Z, 080900Z AND 081500Z.// ========================================================================= WTPS31 PGTW 20170507 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 017// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 017 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 071800Z --- NEAR 16.5S 164.8E MOVEMENT PAST SIX HOURS - 180 DEGREES AT 10 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: 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 - 070 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 075 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT REPEAT POSIT: 16.5S 164.8E --- FORECASTS: 12 HRS, VALID AT: 080600Z --- 18.2S 165.3E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 115 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 160 DEG/ 09 KTS --- 24 HRS, VALID AT: 081800Z --- 19.9S 166.0E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 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 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 155 DEG/ 09 KTS --- 36 HRS, VALID AT: 090600Z --- 21.6S 166.9E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 140 DEG/ 10 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 091800Z --- 23.1S 168.3E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 13 KTS --- 72 HRS, VALID AT: 101800Z --- 26.8S 172.1E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT --- REMARKS: 072100Z POSITION NEAR 16.9S 164.9E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 213 NM WEST- NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWARD AT 10 KNOTS OVER THE PAST SIX HOURS. AFTER DAYS OF SLOW OR STALLED DEVELOPMENT, ANIMATED ENHANCED INFRARED SATELLITE IMAGERY INDICATES TC 18P HAS IMPROVED ITS OVERALL CONVECTIVE ORGANIZATION AND MAINTAINED A RAGGED 25 NM DIAMETER EYE DURING A PERIOD OF PRONOUNCED INTENSIFICATION. THE INITIAL POSITION IS BASED ON EYE FIXES WITH HIGH CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 115 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T6.0 (115 KNOTS) FROM KNES AND NFFN. THE PGTW DVORAK ESTIMATE IS T6.5, HOWEVER, AN ASSESSMENT OF RECENT 89 GHZ MICROWAVE IMAGERY DOES NOT SUPPORT THAT RANGE AT THIS TIME. TC DONNA IS CURRENTLY TRACKING SOUTH-SOUTHEASTWARD UNDER THE INFLUENCE OF A WELL-ESTABLISHED SUB-TROPICAL RIDGE TO THE EAST. THIS MOTION IS EXPECTED TO CONTINUE OVER THE NEXT 36 HOURS BEFORE BECOMING MORE SOUTHEASTWARD LATER IN THE FORECAST PERIOD IN RESPONSE TO AN APPROACHING SHORTWAVE TROUGH. DYNAMIC GUIDANCE REMAINS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. ENVIRONMENTAL CONDITIONS, INCLUDING LIGHT VERTICAL WIND SHEAR (VWS), ROBUST POLEWARD OUTFLOW, AND WARM SST WATERS WILL PERSIST OVER THE NEXT 12 HOURS ALLOWING THE SYSTEM TO REMAIN NEAR ITS CURRENT INTENSITY. BETWEEN TAUS 24 TO 36, SSTS WILL BEGIN TO FALL AND LAND INTERACTION WITH NEW CALEDONIA WILL INCREASE, INITIATING A SLOW DISSIPATION. BY TAU 36, TC 18P WILL BEGIN EXTRA-TROPICAL TRANSITION AND RAPIDLY WEAKEN AS IT MOVES OVER SUB-26 DEGREE CELSIUS WATER AND INTERACTS WITH MIDLATITUDE WESTERLIES AND THE WEAK BAROCLINIC ZONE. THE SYSTEM IS EXPECTED TO COMPLETE EXTRA-TROPICAL TRANSITION AT THE END OF THE FORECAST AS IT BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 071800Z IS 32 FEET. NEXT WARNINGS AT 080300Z, 080900Z, 081500Z AND 082100Z. ========================================================================= WTPS31 PGTW 20170508 03:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 018// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 018 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 080000Z --- NEAR 16.9S 164.8E MOVEMENT PAST SIX HOURS - 180 DEGREES AT 04 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: 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 045 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT REPEAT POSIT: 16.9S 164.8E --- FORECASTS: 12 HRS, VALID AT: 081200Z --- 18.3S 165.4E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 195 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 155 DEG/ 08 KTS --- 24 HRS, VALID AT: 090000Z --- 19.7S 166.1E 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 030 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 150 DEG/ 09 KTS --- 36 HRS, VALID AT: 091200Z --- 21.2S 167.0E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 145 DEG/ 10 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 100000Z --- 22.8S 168.3E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 12 KTS --- 72 HRS, VALID AT: 110000Z --- 26.2S 171.8E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT --- REMARKS: 080300Z POSITION NEAR 17.2S 164.9E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 206 NM WEST- NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TIGHTLY CURVED BANDING WRAPPING INTO A WELL DEFINED AND SYMMETRIC 30 NM EYE, WITH A LARGE CONVECTIVE ASYMMETRY IN THE SOUTHEAST QUADRANT. THE INITIAL POSITION IS BASED ON EYE FIXES WITH HIGH CONFIDENCE. A 072254Z AMSU 89 GHZ IMAGE REVEALS A SOLID CORE OF DEEP CONVECTION COMPLETELY SURROUNDING THE EYE. THE INITIAL INTENSITY IS ASSESSED AT 115 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T6.0 (115 KNOTS) FROM PGTW, ABRF, AND PHFO, AND IS SUPPORTED BY CIMSS SATCON. TC DONNA IS CURRENTLY TRACKING UNDER THE STEERING INFLUENCE OF A WELL-ESTABLISHED SUB-TROPICAL RIDGE TO THE EAST, WITH MOTION EXPECTED TO BECOME SOUTH-SOUTHEASTERLY TO SOUTHEASTERLY AS THE STR RE-ORIENTS IN RESPONSE TO AN APPROACHING SHORTWAVE TROUGH. THE MULTI-MODEL CONSENSUS MEMBERS REMAIN IN MOSTLY GOOD AGREEMENT AND ENSEMBLE MODEL SPREAD IS GENERALLY LOW, LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. ENVIRONMENTAL CONDITIONS, INCLUDING LIGHT VERTICAL WIND SHEAR (VWS), ROBUST POLEWARD OUTFLOW, AND WARM SST WATERS WILL PERSIST OVER THE NEXT 12 HOURS ALLOWING THE SYSTEM TO REMAIN NEAR ITS CURRENT INTENSITY. BETWEEN TAUS 24 TO 36, SSTS WILL BEGIN TO FALL AND LAND INTERACTION WITH NEW CALEDONIA WILL INCREASE, INITIATING A SLOW DISSIPATION. BY TAU 36, TC 18P WILL BEGIN EXTRA-TROPICAL TRANSITION AND RAPIDLY WEAKEN AS IT MOVES OVER SUB-26 DEGREE CELSIUS WATER AND INTERACTS WITH MIDLATITUDE WESTERLIES AND THE WEAK BAROCLINIC ZONE. THE SYSTEM IS EXPECTED TO COMPLETE EXTRA-TROPICAL TRANSITION AT THE END OF THE FORECAST AS IT BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 080000Z IS 27 FEET. NEXT WARNINGS AT 080900Z, 081500Z, 082100Z, AND 090300Z. ========================================================================= WTPS31 PGTW 20170508 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 019 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 080600Z --- NEAR 17.5S 165.1E MOVEMENT PAST SIX HOURS - 155 DEGREES AT 07 KTS POSITION ACCURATE TO WITHIN 020 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT REPEAT POSIT: 17.5S 165.1E --- FORECASTS: 12 HRS, VALID AT: 081800Z --- 18.8S 165.8E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 195 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 155 DEG/ 08 KTS --- 24 HRS, VALID AT: 090600Z --- 20.3S 166.6E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 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 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 145 DEG/ 09 KTS --- 36 HRS, VALID AT: 091800Z --- 21.8S 167.7E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 140 DEG/ 12 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 100600Z --- 23.7S 169.3E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 15 KTS --- 72 HRS, VALID AT: 110600Z --- 28.2S 174.0E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT --- REMARKS: 080900Z POSITION NEAR 17.8S 165.3E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 183 NM WEST OF PORT VILA, VANUATU, HAS TRACKED SOUTH-SOUTHEASTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. AFTER A PERIOD OF RAPID INTENSIFICATION, TC 18P APPEARS TO BE WEAKENING SLIGHTLY WITH THE EYE BECOMING CLOUD- FILLED AND CORE CONVECTION INCREASINGLY ASYMMETRIC. A 080446Z SSMIS 91 GHZ IMAGE INDICATES EROSION OF EYEWALL CONVECTION OVER THE WEST QUADRANT WITH THE BULK OF DEEP CONVECTION NOW OVER THE SOUTHERN SEMI- CIRCLE. TC 18P PEAKED EARLIER NEAR 120 KNOTS BUT IS NOW ASSESSED AT 115 KNOTS BASED ON THE LOWER END OF DVORAK ESTIMATES RANGING FROM 115 TO 127 KNOTS (T6.0 TO 6.5), CONSISTENT WITH THE CONVECTIVE STRUCTURE. TC 18P IS FORECAST TO TRACK SOUTH-SOUTHEASTWARD THROUGH THE FORECAST PERIOD ALONG THE WESTERN PERIPHERY OF A NORTH-SOUTH ORIENTED SUBTROPICAL RIDGE. DYNAMIC GUIDANCE REMAINS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE TO THE FORECAST TRACK. TC DONNA IS EXPECTED TO WEAKEN GRADUALLY AS IT TRACKS EAST OF NEW CALEDONIA DUE TO COOLER SST AND LAND INTERACTION. AFTER TAU 24, THE SYSTEM WILL BEGIN EXTRA-TROPICAL TRANSITION (ETT) AS IT INTERACTS WITH A MAJOR SHORTWAVE TROUGH AND BAROCLINIC ZONE. RAPID WEAKENING IS EXPECTED AFTER TAU 36 DUE TO STRONG VERTICAL WIND SHEAR AND COLD SST. TC 18P SHOULD COMPLETE ETT BY TAU 60. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 080600Z IS 27 FEET. NEXT WARNINGS AT 081500Z, 082100Z, 090300Z AND 090900Z.// ========================================================================= WTPS31 PGTW 20170508 15:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 020 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 081200Z --- NEAR 18.0S 165.7E MOVEMENT PAST SIX HOURS - 130 DEGREES AT 08 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT REPEAT POSIT: 18.0S 165.7E --- FORECASTS: 12 HRS, VALID AT: 090000Z --- 19.3S 166.5E 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 030 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 150 DEG/ 09 KTS --- 24 HRS, VALID AT: 091200Z --- 20.8S 167.4E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 005 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 075 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 145 DEG/ 11 KTS --- 36 HRS, VALID AT: 100000Z --- 22.5S 168.8E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 005 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 140 DEG/ 14 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 101200Z --- 24.6S 170.8E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 15 KTS --- 72 HRS, VALID AT: 111200Z --- 29.0S 175.4E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 215 NM NORTHEAST QUADRANT 235 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT --- REMARKS: 081500Z POSITION NEAR 18.3S 165.9E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 150 NM WEST OF PORT VILA, VANUATU, HAS TRACKED SOUTHEASTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY SHOWS THAT TC 18P HAS BEGUN TO WEAKEN SIGNIFICANTLY WITH A MORE ASYMMETRIC CONVECTIVE STRUCTURE. A 081030Z METOP-A 89 GHZ IMAGE INDICATES EROSION OF EYEWALL CONVECTION OVER THE WESTERN SEMI-CIRCLE AND A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION CENTER. CONSEQUENTLY, THE CURRENT INTENSITY IS ASSESSED AT 105 KNOTS BASED ON THE LOWER END OF DVORAK ESTIMATES RANGING FROM 102 TO 127 KNOTS. TC 18P IS FORECAST TO TRACK SOUTH-SOUTHEASTWARD THROUGH THE FORECAST PERIOD ALONG THE WESTERN PERIPHERY OF A NORTH-SOUTH ORIENTED SUBTROPICAL RIDGE. DYNAMIC GUIDANCE REMAINS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE TO THE FORECAST TRACK. TC DONNA IS EXPECTED TO WEAKEN FURTHER AS IT TRACKS EAST OF NEW CALEDONIA DUE TO COOLER SST AND LAND INTERACTION. AFTER TAU 24, THE SYSTEM WILL BEGIN EXTRA-TROPICAL TRANSITION (ETT) AS IT INTERACTS WITH A MAJOR SHORTWAVE TROUGH AND BAROCLINIC ZONE. RAPID WEAKENING IS EXPECTED AFTER TAU 36 DUE TO STRONG VERTICAL WIND SHEAR AND COLD SST. TC 18P SHOULD COMPLETE ETT BY TAU 60. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 081200Z IS 27 FEET. NEXT WARNINGS AT 082100Z, 090300Z, 090900Z AND 091500Z.// ========================================================================= WTPS31 PGTW 20170508 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 021// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 021 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 081800Z --- NEAR 18.7S 166.1E MOVEMENT PAST SIX HOURS - 150 DEGREES AT 08 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT REPEAT POSIT: 18.7S 166.1E --- FORECASTS: 12 HRS, VALID AT: 090600Z --- 20.0S 166.9E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 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 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 145 DEG/ 10 KTS --- 24 HRS, VALID AT: 091800Z --- 21.6S 168.0E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 005 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 140 DEG/ 13 KTS --- 36 HRS, VALID AT: 100600Z --- 23.6S 169.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 140 DEG/ 14 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 101800Z --- 25.7S 171.6E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 15 KTS --- 72 HRS, VALID AT: 111800Z --- 30.3S 175.8E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL --- REMARKS: 082100Z POSITION NEAR 19.0S 166.3E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 139 NM WEST- SOUTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTH-SOUTHEASTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS TC 18P WEAKENING WITH ASYMMETRIC CONVECTIVE BANDING. THE CURRENT INTENSITY IS ASSESSED AT 100 KNOTS WHICH IS HEDGED ON THE LOWER END OF THE PGTW DVORAK FIX OF T5.5. THE SYSTEM IS CURRENTLY IN AN AREA OF LOW VERTICAL WIND SHEAR (VWS), HIGH SEA SURFACE TEMPERATURES (SSTS 27-28C), AND HAS STRONG POLEWARD OUTFLOW WITH WEAKER EQUATORWARD OUTFLOW. TC 18P IS FORECAST TO TRACK SOUTH-SOUTHEASTWARD FOR THE DURATION OF THE FORECAST PERIOD UNDER THE INFLUENCE OF A SUBTROPICAL RIDGE LOCATED TO THE EAST. AS TC DONNA TRACKS TO THE SOUTH IT WILL MOVE INTO AN AREA OF COOLER SSTS AND INCREASING VWS ASSOCIATED WITH A STRONG SHORTHWAVE TROUGH THAT WILL CONTINUE TO ERODE THE CYCLONE. THE INTERACTION WITH THE TROUGH AND ITS ASSOCIATED BAROCLINIC ZONE WILL CONCURRENTLY CAUSE THE SYSTEM TO BEGIN EXTRA-TROPICAL TRANSITION WHICH WILL BE COMPLETED BY THE END OF THE FORECAST PERIOD. THE DYNAMIC GUIDANCE IS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 081800Z IS 30 FEET. NEXT WARNINGS AT 090300Z, 090900Z, 091500Z AND 092100Z.// ========================================================================= WTPS31 PGTW 20170509 03:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 022// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 022 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 090000Z --- NEAR 19.5S 166.6E MOVEMENT PAST SIX HOURS - 150 DEGREES AT 09 KTS POSITION ACCURATE TO WITHIN 015 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 065 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT REPEAT POSIT: 19.5S 166.6E --- FORECASTS: 12 HRS, VALID AT: 091200Z --- 21.0S 167.4E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 075 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 120 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 205 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 160 DEG/ 09 KTS --- 24 HRS, VALID AT: 100000Z --- 22.6S 168.1E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 135 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 155 DEG/ 09 KTS --- 36 HRS, VALID AT: 101200Z --- 24.3S 168.9E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 145 DEG/ 18 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 110000Z --- 27.3S 171.1E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT --- REMARKS: 090300Z POSITION NEAR 19.9S 166.8E. TROPICAL CYCLONE (TC) 18P (DONNA), LOCATED APPROXIMATELY 159 NM OF NOUMEA, NEW CALEDONIA, HAS TRACKED SOUTH-SOUTHEASTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS TC 18P WEAKENING WITH ASYMMETRIC CONVECTIVE BANDING. THE CURRENT INTENSITY IS ASSESSED AT 95 KNOTS WHICH IS HEDGED ON THE LOWER END OF AGENCY CURRENT INTENSITY DVORAK FIXES RANGING FROM T5.0 TO T6.0 (90 TO 115 KNOTS). THE SYSTEM IS CURRENTLY IN AN AREA OF LOW VERTICAL WIND SHEAR (VWS), HIGH SEA SURFACE TEMPERATURES (SSTS 27- 28C), AND HAS STRONG POLEWARD OUTFLOW WITH WEAKER EQUATORWARD OUTFLOW. TC 18P IS FORECAST TO TRACK SOUTH-SOUTHEASTWARD FOR THE DURATION OF THE FORECAST PERIOD UNDER THE INFLUENCE OF A SUBTROPICAL RIDGE LOCATED TO THE EAST. AS TC DONNA TRACKS TO THE SOUTH IT WILL MOVE INTO AN AREA OF COOLER SSTS AND INCREASING VWS ASSOCIATED WITH A STRONG SHORTWAVE TROUGH THAT WILL CONTINUE TO ERODE THE CYCLONE. THE INTERACTION WITH THE TROUGH AND ITS ASSOCIATED BAROCLINIC ZONE WILL CONCURRENTLY CAUSE THE SYSTEM TO BEGIN EXTRA-TROPICAL TRANSITION WHICH WILL BE COMPLETED BY THE END OF THE FORECAST PERIOD. THE DYNAMIC GUIDANCE IS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK MAXIMUM SIGNIFICANT WAVE HEIGHT AT 090000Z IS 28 FEET. NEXT WARNINGS AT 090600, 091500Z, 092100, AND 100300Z.// ========================================================================= WTPS31 PGTW 20170509 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 023// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 023 02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 090600Z --- NEAR 20.1S 167.3E MOVEMENT PAST SIX HOURS - 130 DEGREES AT 09 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 - 055 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT REPEAT POSIT: 20.1S 167.3E --- FORECASTS: 12 HRS, VALID AT: 091800Z --- 21.6S 168.0E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 155 DEG/ 09 KTS --- 24 HRS, VALID AT: 100600Z --- 23.2S 168.8E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 150 DEG/ 13 KTS --- 36 HRS, VALID AT: 101800Z --- 25.4S 170.2E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 145 DEG/ 19 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 110600Z --- 28.4S 172.7E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT --- REMARKS: 090900Z POSITION NEAR 20.5S 167.5E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 138 NM NORTH- NORTHEAST OF NOUMEA, NEW CALEDONIA, HAS TRACKED SOUTHEASTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A RAPIDLY WEAKENING SYSTEM WITH WARMING CLOUD TOPS. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE EXTRAPOLATED FROM A RAGGED EYE FEATURE OBSERVED IN A 090432Z 91 GHZ SSMIS IMAGE. THE INITIAL INTENSITY ASSESSMENT OF 90 KNOTS IS BASED ON THE LOWER ENVELOP OF MULTI-AGENCY CURRENT INTENSITY DVORAK ESTIMATES RANGING FROM T5.0 TO T5.5 (90 TO 102 KNOTS). ENVIRONMENTAL CONDITIONS CONTINUE TO DETERIORATE AND WILL WEAKEN THE SYSTEM SIGNIFICANTLY OVER THE NEXT 48 HOURS. AN APPROACHING TROUGH FROM THE WEST IS INTRODUCING STRONG WESTERLY FLOW ALOFT, THUS IMPEDING THE POLEWARD EXHAUST CHANNEL AND WILL STEADILY INCREASE VERTICAL WIND SHEAR THROUGHOUT THE FORECAST PERIOD. TC DONNA IS ALSO DRIFTING INTO COOLER WATERS AND THIS TREND WILL CONTINUE ALONG THE FORECAST TRACK. TC DONNA WILL CONTINUE TRACKING SOUTHEASTWARD INTO THE BAROCLINIC REGION OF THE APPROACHING TROUGH AND BEGIN TRANSITIONING INTO AN EXTRATROPICAL SYSTEM IN THE NEXT 24 TO 36 HOURS. TC DONNA WILL BECOME EXTRATROPICAL BY TAU 48. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 090600Z IS 28 FEET. NEXT WARNINGS AT 092100Z AND 100900Z. REFER TO TROPICAL CYCLONE 19P (ELLA) WARNINGS (WTPS32 PGTW) FOR SIX-HOURLY UPDATES.// ========================================================================= WTPS31 PGTW 20170509 21:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 024// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 024 02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 091800Z --- NEAR 21.1S 166.8E MOVEMENT PAST SIX HOURS - 155 DEGREES AT 07 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT REPEAT POSIT: 21.1S 166.8E --- FORECASTS: 12 HRS, VALID AT: 100600Z --- 22.7S 168.0E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 145 DEG/ 12 KTS --- 24 HRS, VALID AT: 101800Z --- 24.7S 169.5E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 140 DEG/ 18 KTS --- 36 HRS, VALID AT: 110600Z --- 27.5S 172.1E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT --- REMARKS: 092100Z POSITION NEAR 21.5S 167.1E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 72 NM NORTH- NORTHEAST OF NOUMEA, NEW CALEDONIA, HAS TRACKED SOUTH-SOUTHEASTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (IR) SATELLITE IMAGERY DEPICTS A RAPIDLY WEAKENING SYSTEM WITH CONVECTION THAT IS SIGNIFICANTLY SHEARED FROM THE LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH FAIR CONFIDENCE BASED ON THE PARTIALLY EXPOSED LLCC EVIDENT IN THE IR ANIMATION. THE CURRENT INTENSITY ASSESSMENT OF 60 KNOTS IS BASED ON MULTI-AGENCY DVORAK ESTIMATES RANGING FROM T3.0 TO T4.0 (45 TO 65 KNOTS). POOR ENVIRONMENTAL CONDITIONS WILL PERSIST FOR THE DURATION OF THE FORECAST PERIOD AS STRONG VERTICAL WIND SHEAR ERODES THE SYSTEM. ADDITIONALLY, TC DONNA IS TRACKING INTO COOLER WATERS AS IT MOVES SOUTH. TC 18P IS CURRENTLY UNDER THE INFLUENCE OF A RIDGE TO THE EAST THAT HAS CAUSED THE SYSTEM TO TRACK TO THE SOUTHWEST BEFORE RESUMING ITS MOVEMENT TO THE SOUTHEAST. TC DONNA WILL CONTINUE ON THIS SOUTHEASTWARD TRACK AND TRANSITION INTO AN EXTRA-TROPICAL SYSTEM WITHIN THE NEXT 24-36 HOURS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 091800Z IS 18 FEET. NEXT WARNINGS AT 100900Z AND 102100Z. REFER TO TROPICAL CYCLONE 19P (ELLA) WARNINGS (WTPS32 PGTW) FOR TWELVE- HOURLY UPDATES.// ========================================================================= WTPS31 PGTW 20170510 09:00z MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18P (DONNA) WARNING NR 025// RMKS/ 1. TROPICAL CYCLONE 18P (DONNA) WARNING NR 025 02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 100600Z --- NEAR 22.9S 168.0E MOVEMENT PAST SIX HOURS - 175 DEGREES AT 15 KTS POSITION ACCURATE TO WITHIN 020 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 DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT REPEAT POSIT: 22.9S 168.0E --- FORECASTS: 12 HRS, VALID AT: 101800Z --- 25.6S 168.7E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 100900Z POSITION NEAR 23.6S 168.2E. TROPICAL CYCLONE 18P (DONNA), LOCATED APPROXIMATELY 116 NM EAST- SOUTHEAST OF NOUMEA, NEW CALEDONIA, HAS TRACKED SOUTHWARD AT 15 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS AN ELONGATED AND RAPIDLY DETERIORATING FULLY EXPOSED LOW LEVEL CIRCULATION CENTER. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE MENTIONED SATELLITE IMAGERY. AGENCY DVORAK INTENSITY ESTIMATES HAVE COME DOWN SIGNIFICANTLY IN THE LAST TWELVE HOURS AND A RECENT T2.5 (35 KNOTS) ESTIMATE COMBINED WITH LOCAL SURFACE OBSERVATIONS FROM MARE ISLAND IS THE BASIS FOR THE INITIAL INTENSITY ASSESSMENT OF 35 KNOTS. ENVIRONMENTAL CONDITIONS HAVE DETERIORATED SIGNIFICANTLY AND TC DONNA IS EXPECTED TO WEAKEN FURTHER WHILE TRACKING SOUTHWARD OVER THE NEXT 12 HOURS. THIS IS THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON WRNCEN PEARL HARBOR HI. THE SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 100600Z IS 12 FEET. REFER TO TROPICAL CYCLONE 19P (ELLA) WARNINGS (WTPS32 PGTW) FOR SIX- HOURLY UPDATES.//
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Document: tropical_cyclone_donna.htm | Updated: 22 May 2017 |