Typhoon 08W(AMPIL) peaked at CAT 4 US//INVEST 98W//INVEST 90S//HU 05L(ERNESTO) peaks at CAT 2 US//1703utc

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON 08W. 3HOURLY SATELLITE BULLETINS ARE ISSUED ON 90S.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: HOW THE MIGHTY HAVE FALLEN, ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS RAPIDLY DISINTEGRATING CONVECTIVE BANDING THROUGHOUT THE WESTERN SEMICIRCLE OF THE SYSTEM. AS COOL DRY AIR CONTINUES TO BATTER THE SYSTEM, CENTRAL CONVECTION WILL STRUGGLE TO MAINTAIN ORGANIZATION AS THE SYSTEM INCREASES ITS POLEWARD TRANSLATION. A 162141Z SUITE OF SSMIS MICROWAVE IMAGERY INDICATE THE SYSTEM IS TILTED WITH HEIGHT AND DEVOID OF MUCH OF THE ORGANIZED CONVECTION IT POSSESSED NOT 6 HOURS AGO. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON EIR AND SSMIS IMAGERY. THE INITIAL INTENSITY OF 100 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE MAJORITY OF INTENSITY GUIDANCE INDICATES 90-102KTS WHILE CIMSS DPRINT AND ADT INDICATE BELOW 85KTS, WHICH IS TOO BOLD.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: 08W (AMPIL) IS FORECASTED TO CONTINUE TRACKING ALONG THE NORTHWESTERN PERIPHERY OF THE STR WHICH WILL GUIDE THE SYSTEM NORTHEASTWARD THROUGH THE FORECAST PERIOD. AS THE SYSTEM CONTINUES TO TRACK POLEWARD AND EASTWARD, ITS ENVIRONMENT WILL CONTINUE TO WORSEN. OVER THE PAST FEW HOURS, THE ENTIRE WESTERN SEMICIRCLE OF 08W HAS BEGUN TO ERODE UNDER PERSISTENT NORTHERLY FLOW. NEAR TAU 24, 08W WILL TRACK POLEWARD OF THE 26C ISOTHERM WHICH WILL FURTHER EXACERBATE THE WEAKENING TREND. NEAR TAU 36, THE SYSTEM INCREASES ITS INTERACTION WITH THE STRONG BAROCLINIC ZONE ASSOCIATED WITH THE JET MAXIMA, THEREBY INITIATING EXTRATROPICAL TRANSITION. THIS TRANSITION WILL BE SWIFT, BY TAU 48, AS 08W IS RAPIDLY INCORPORATED INTO AND POLEWARD OF THE SUBTROPICAL JET, 08W WILL BECOME A COLD CORE BAROCLINIC LOW, DEVOID OF ANY SUBTROPICAL CHARACTERISTIC.

MODEL DISCUSSION: NUMERICAL MODELS ARE IN EXCELLENT AGREEMENT, SHOWING A 30NM CROSS TRACK SPREADING AT TAU 24 THAT BECOMES 82NM AT TAU 48. FOR THIS REASON, THE JTWC FORECAST TRACK IS PLACED WITH HIGH CONFIDENCE. RELIABLE MODEL INTENSITY GUIDANCE IS ALSO IN TIGHT AGREEMENT WITH ALL MEMBERS INDICATING A STEADY WEAKENING TREND THROUGH THE FORECAST PERIOD WITH MINIMAL DEVIATION. FOR THIS REASON, THE JTWC INTENSITY FORECAST IS ALSO PLACED WITH HIGH CONFIDENCE.

AN AREA OF CONVECTION (INVEST 98W) HAS PERSISTED NEAR 25.0N 122.4E, APPROXIMATELY 51 NM EAST OF TAIPEI. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND A 162146Z SSMIS 91GHZ MICROWAVE IMAGE REVEALS A POORLY ORGANIZED LLCC, AS WELL AS FLARING CONVECTION ALONG AN AREA OF BROAD AND WEAK CIRCULATION. ENVIRONMENTAL ANALYSIS IS MARGINALLY UNFAVORABLE CHARACTERIZED BY HIGH VERTICAL WIND SHEAR (25-30KTS), WEAK EQUATORWARD OUTFLOW OFFSET BY HIGH SST (28-30C) . DETERMINISTIC MODELS INDICATE THAT THE AREA OF CONVECTION (98W) WILL SLOWLY DEVELOP OVER THE NEXT 48-72 HOURS AS IT TRANSITS NORTHEASTWARD. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 13 TO 18 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.

DETERMINISTIC MODELS INDICATE THAT THE AREA OF CONVECTION (98W) WILL SLOWLY DEVELOP OVER THE NEXT 48-72 HOURS AS IT TRANSITS NORTHEASTWARD

THE AREA OF CONVECTION (INVEST 90S) PREVIOUSLY LOCATED NEAR 43.0S 74.5E IS NOW LOCATED NEAR 6.2S 73.4E, APPROXIMATELY 54 NM NORTHEAST OF DIEGO GARCIA. ENHANCED INFRARED SATELLITE IMAGERY AND 161329Z SSMIS 91GHZ SATELLITE IMAGERY DEPICTS AN AREA OF FLARING CONVECTION, WITH A PARTIALLY EXPOSED LOW LEVEL CIRCULATION WITH PERSISTENT CONVECTION. ENVIRONMENTAL ANALYSIS REVEALS AN AREA THAT IS MARGINAL FOR DEVELOPMENT WITH, WARM (28-29C) SEA SURFACE TEMPERATURES, HIGH (30-40 KTS) VERTICAL WIND SHEAR, AND WEAK EQUATORWARD OUTFLOW ALOFT. GLOBAL MODELS ARE IN AGREEMENT THAT INVEST 90S WILL CONTINUE TO GRADUALLY INTENSIFY AND GENERALLY TRACK SOUTHWESTWARD OVER THE NEXT 24- 48 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 28 TO 33 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS HIGH.

GLOBAL MODELS ARE IN AGREEMENT THAT INVEST 90S WILL CONTINUE TO GRADUALLY INTENSIFY AND GENERALLY TRACK SOUTHWESTWARD OVER THE NEXT 24- 48 HOURS.