WTPS31 PGTW 310900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 06P (ULA) WARNING NR 003// RMKS/ 1. TROPICAL CYCLONE 06P (ULA) 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: 310600Z --- NEAR 15.5S 169.0W MOVEMENT PAST SIX HOURS - 250 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 010 NM POSITION BASED ON EYE FIXED 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 - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT REPEAT POSIT: 15.5S 169.0W --- FORECASTS: 12 HRS, VALID AT: 311800Z --- 16.4S 170.5W MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 240 DEG/ 10 KTS --- 24 HRS, VALID AT: 010600Z --- 17.4S 172.4W MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 075 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 260 DEG/ 13 KTS --- 36 HRS, VALID AT: 011800Z --- 17.9S 175.1W MAX SUSTAINED WINDS - 075 KT, GUSTS 090 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 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 260 DEG/ 10 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 020600Z --- 18.2S 177.2W MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 250 DEG/ 05 KTS --- 72 HRS, VALID AT: 030600Z --- 19.0S 179.3W MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 225 DEG/ 04 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 040600Z --- 20.1S 179.5E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER VECTOR TO 120 HR POSIT: 215 DEG/ 03 KTS --- 120 HRS, VALID AT: 050600Z --- 21.1S 178.8E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 310900Z POSITION NEAR 15.7S 169.4W. TROPICAL CYCLONE 06P (ULA), LOCATED APPROXIMATELY 122 NM SOUTHEAST OF PAGO PAGO, AMERICAN SAMOA HAS TRACKED WEST- SOUTHWESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS A MORE SYMMETRIC CONVECTIVE CORE WITH DEEP SPIRAL BANDING WRAPPING IN FROM ALL QUADRANTS. THE ANIMATED ENHANCED INFRARED LOOP HAS SHOWN EVIDENCE OF A DEVELOPING PINHOLE EYE FEATURE. A 310608Z SSMIS 91GHZ IMAGE FURTHER ILLUSTRATES THE IMPROVED CONVECTIVE STRUCTURE WITH THE MOST INTENSE BANDING ALONG THE EASTERN PERIPHERY AND A SMALL MICROWAVE EYE FEATURE WHICH SUPPORTS THE CURRENT POSITION WITH HIGH CONFIDENCE. THE INTENSITY HAS BEEN INCREASED TO 55 KNOTS BASED ON INCREASING DVORAK INTENSITY ESTIMATES FROM ALL AGENCIES AND SUPPORTS THE IMPROVED STRUCTURE OF THE SYSTEM. UPPER LEVEL ANALYSIS REVEALS A FAVORABLE ENVIRONMENT WITH LOW VERTICAL WIND SHEAR (VWS) AND RADIAL OUTFLOW CAUSED BY A POINT SOURCE OVER THE CYCLONE. TC 06P IS TRACKING WESTWARD ALONG THE NORTHERN PERIPHERY OF A BUILDING SUB-TROPICAL RIDGE (STR) TO THE SOUTH. THIS STR WILL REMAIN THE DOMINANT STEERING MECHANISM THROUGHOUT THE FORECAST PERIOD. ENVIRONMENTAL CONDITIONS WILL REMAIN FAVORABLE OVER THE NEXT 48 HOURS SUPPORTING CONTINUED INTENSIFICATION. BEYOND TAU 48, AN APPROACHING MID-LATITUDE TROUGH WILL CREATE INCREASED VWS WHICH WILL BEGIN THE WEAKENING TREND. THE SYSTEM WILL THEN TURN POLEWARD AND DISSIPATE BY THE END OF THE FORECAST PERIOD DUE TO THE STRONG VWS AND SUBSIDENCE ALOFT. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT THROUGH TAU 72. AFTERWARDS, A FEW MODEL TRACKERS STRUGGLE TO TRACK THE VORTEX SIGNATURE AS THE CYCLONE IS WEAKENING WHICH HAS CAUSED A SLIGHT SPREAD. HOWEVER, BASED ON THE GOOD OVERALL MODEL AGREEMENT, THERE REMAINS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 310600Z IS 22 FEET. NEXT WARNINGS AT 312100Z AND 010900Z.//