REMARKS: 210300Z POSITION NEAR 21.3S 63.7E. TROPICAL CYCLONE (TC) 07S (ETHEL), LOCATED APPROXIMATELY 355 NM EAST OF PORT LOUIS, HAS TRACKED SOUTHWARD AT 09 KNOTS OVER THE PAST 06 HOURS. ANIMATED INFRARED SATELLITE IMAGERY INDICATES SLIGHT WEAKENING IN THE CONVECTIVE ORGANIZATION OVER THE PAST 12 HOURS WITH WARMING CLOUD TOPS AND MORE ELONGATED CENTRAL CONVECTION. A 202238Z TRMM 37GHZ IMAGE CONTINUES TO INDICATE TIGHTLY-CURVED BANDING AND A MICROWAVE EYE FEATURE BUT THE LOW-LEVEL CIRCULATION CENTER HAS BECOME MORE ASYMMETRIC WITH THE BULK OF THE DEEP CONVECTION DISPLACED OVER THE WESTERN SEMI-CIRCLE DUE TO NORTHEASTERLY VERTICAL WIND SHEAR (VWS). DESPITE THE WEAKENING TREND, THE CURRENT INTENSITY REMAINS AT 75 KNOTS BASED ON DVORAK CURRENT INTENSITY ESTIMATES OF 77 KNOTS. THE CURRENT POSITION IS BASED ON THE TRMM IMAGE AS WELL AS A 202315Z SSMI IMAGE WITH GOOD CONFIDENCE. TC 07S IS TRACKING SOUTHWARD ALONG THE WESTERN PERIPHERY OF A NORTH-SOUTH ORIENTED SUBTROPICAL RIDGE (STR) AND IS FORECAST TO TRACK INCREASINGLY SOUTHEASTWARD AFTER TAU 36 AS IT BEGINS TO RE-CURVE AND ACCELERATE INTO THE MIDLATITUDE WESTERLIES. TC 07S WILL WEAKEN RAPIDLY AFTER TAU 36 DUE TO INCREASING VWS AND COOLER SST (LESS THAN 26C). THE SYSTEM IS EXPECTED TO BEGIN EXTRA-TROPICAL TRANSITION (ETT) NEAR TAU 36 AND WILL COMPLETE ETT BETWEEN TAU 60 AND TAU 72 AS IT BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT. THE JTWC TRACK IS SLIGHTLY FASTER AND FURTHER EAST THAN THE MODEL CONSENSUS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210000Z IS 21 FEET. NEXT WARNINGS AT 211500Z AND 220300Z. REFER TO TROPICAL CYCLONE 08S (FUNSO) WARNINGS (WTXS32 PGTW) FOR TWELVE- HOURLY UPDATES.// 減弱,後期轉化為溫氣 巔峰為75KTS |
REMARKS:200300Z POSITION NEAR 18.2S 64.9E.TROPICAL CYCLONE (TC) 07S (ETHEL) LOCATED APPROXIMATELY 580 NM EAST-NORTHEAST OF LA REUNION, HAS TRACKED SOUTHWESTWARD AT 10 KNOTS OVER THE PAST 06 HOURS. ANIMATED INFRARED SATELLITE IMAGERY HAS SHOWN A SIGNIFICANT INCREASE IN THE OVERALL STRUCTURE OF TC 07S WITH BUILDING DEEP CONVECTION WRAPPING INTO THE LOW LEVEL CIRCULATION CENTER (LLCC). THE CURRENT INTENSITY WAS BASED ON A MIX OF DVORAK FIXES RANGING FROM 65 TO 77 KNOTS. ANIMATED WATER VAPOR IMAGERY HAS SHOWN THE EQUATORWARD RADIAL OUTFLOW HAS CONTINUED TO PROVIDE AMPLE VENTILATION TO THE LLCC WITH AN IMPROVING POLEWARD OUTFLOW CHANNEL. THE INCREASE IN POLEWARD OUTFLOW WILL BE SHORT LIVED AS TC 07S CONTINUES TO TRACK SOUTHWEST AROUND THE MID-LEVEL SUBTROPICAL RIDGE, LOCATED TO THE EAST, DUE TO GREATER INTERACTION WITH A MID-LATITUDE TROUGH STIFLING POLEWARD OUTFLOW. DECREASING OUTFLOW, DECREASING SURFACE TEMPERATURES, AND INCREASING VERTICAL WIND SHEAR WILL BEGIN TO WEAKEN THE SYSTEM BEYOND TAU 36. EXTRATROPICAL TRANSITION IS CURRENTLY FORECASTED TO BEGIN AROUND TAU 48 AND IS EXPECTED TO COMPLETE BETWEEN TAU 96 AND TAU 120. MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THIS FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 200000Z IS 17 FEET. NEXT WARNINGS AT 201500Z AND 210300Z. REFER TO TROPICAL CYCLONE 08S (FUNSO) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.// JTWC第3報上看90KTS |