|
Show Selection: |
| #45556 (Received by flhurricane at: 5:14 PM 12.Sep.2005) TCDAT1 TROPICAL STORM OPHELIA DISCUSSION NUMBER 26 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 5 PM EDT MON SEP 12 2005 THE INNER CORE OF THE TROPICAL CYCLONE HAS BEEN MOSTLY OBLITERATED...WITH THE STRONGEST WINDS OCCURRING IN BANDS 50-60 N MI OR MORE AWAY FROM THE CENTER. SINCE DEEP CONVECTION IS NOT VERY EXTENSIVE...IT IS LIKELY THAT THE SYSTEM IS NOT VERY EFFECTIVE AT MIXING STRONG WINDS DOWN TO THE SURFACE. RECONNAISSANCE FLIGHT LEVEL AND DROPWINDSONDE DATA SUGGEST THAT THE MAXIMUM WINDS REMAIN NEAR 60 KT. OPHELIA IS CROSSING THE GULF STREAM SO THERE IS STILL SOME POTENTIAL FOR RESTRENGTHENING. HOWEVER...UNLESS AND UNTIL THE INNER CORE BECOMES RE-ESTABLISHED...SIGNIFICANT STRENGTHENING IS UNLIKELY. THE OFFICIAL FORECAST ALLOWS FOR THE POSSIBILITY THAT OPHELIA WILL RE-ATTAIN HURRICANE STATUS BEFORE LANDFALL. A SLOW AND MOSTLY NORTHWESTWARD MOTION...AROUND 310/3...HAS BEEN OBSERVED SINCE LATE MORNING. STEERING CURRENTS ARE STILL NOT WELL DEFINED AND THERE IS CONSIDERABLE UNCERTAINTY IN THE TRACK FORECAST. SOME GLOBAL MODELS SUGGEST THAT A MID-LEVEL TROUGH...WHICH COULD POTENTIALLY RECURVE OPHELIA AND TAKE IT NORTHEASTWARD INTO THE ATLANTIC AFTER 3 DAYS...WILL NOT EXTEND FAR ENOUGH SOUTH TO HAVE A SIGNIFICANT EFFECT ON THE TROPICAL CYCLONE. FOR EXAMPLE...THE LATEST NOGAPS GUIDANCE PREDICTS THAT OPHELIA WILL MEANDER OVER/NEAR EASTERN NORTH CAROLINA THROUGH THE END OF THE FORECAST PERIOD. THE GFS IS MOST AGGRESSIVE IN SHOWING THE TROUGH CARRYING OPHELIA NORTHEASTWARD...AND TAKES THE SYSTEM WELL INTO THE NORTH ATLANTIC BY 5 DAYS. THE OFFICIAL FORECAST IS A COMPROMISE OF DIVERSE GUIDANCE BUT DOES INDICATE RECURVATURE...AND A NORTHEASTWARD TRACK INTO THE ATLANTIC. THIS IS CLOSE TO THE GFDL/UKMET/NOGAPS/GFS CONSENSUS. STORM SURGE PREDICTIONS SHOWN IN THE PUBLIC ADVISORY ARE BASED ON A CATEGORY 1 LANDFALL. FORECASTER PASCH FORECAST POSITIONS AND MAX WINDS INITIAL 12/2100Z 31.8N 77.4W 60 KT 12HR VT 13/0600Z 32.3N 77.9W 60 KT 24HR VT 13/1800Z 32.8N 78.0W 65 KT 36HR VT 14/0600Z 33.3N 78.0W 65 KT 48HR VT 14/1800Z 34.2N 77.7W 65 KT 72HR VT 15/1800Z 35.5N 76.0W 65 KT 96HR VT 16/1800Z 38.0N 72.5W 55 KT 120HR VT 17/1800Z 41.0N 67.0W 45 KT...EXTRATROPICAL |
