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#946410 (Received by flhurricane at: 4:50 AM 30.Oct.2018) TCDAT1 Hurricane Oscar Discussion Number 14 NWS National Hurricane Center Miami FL AL162018 500 AM AST Tue Oct 30 2018 Oscar`s eye is less distinct on infrared satellite imagery than it was several hours ago. Conventional and microwave imagery suggest that the center is tilted a bit to the northeast with height, and there continues to be some erosion of convection over the southwestern quadrant of the hurricane. This is indicative of some southwesterly shear over the system, and Oscar does not appear likely to strengthen further. The current intensity is held at 90 kt based on a blend of Dvorak Current Intensity numbers from TAFB and SAB. Model guidance indicates that the shear will not increase further until tonight, so the intensity is held steady for the next 12 hours. After that time, south-southwesterly shear if forecast to increase and become quite high in 36-48 hours. Around that time, global models show Oscar interacting with a frontal zone, and causing significant warm and cold air advection around the center, indicating the transition to a vigorous extratropical cyclone. Not surprisingly, the global guidance also shows a substantial increase in the size of the system during and after the extratropical transformation, and this is reflected in the NHC wind radii forecasts. Oscar is beginning to move faster, just to the east of due north, or around 010/11 kt. There is little change to the track forecast reasoning from the previous advisory. Over the next couple of days, Oscar should continue to accelerate, toward the north-northeast, in the flow on the southeast side of a mid-latitude trough that has just moved off the United States east coast. Later in the period, post-tropical Oscar should become more embedded within the trough and in the mid-latitude westerlies, and move northeastward over the northeastern Atlantic. The official track forecast is similar to the previous one and is a blend of the simple and corrected dynamical model consensus predictions. Large swells from Oscar will affect Bermuda through Wednesday. Please consult products from your local weather office as these conditions could cause life-threatening surf and rip currents. FORECAST POSITIONS AND MAX WINDS INIT 30/0900Z 28.6N 58.2W 90 KT 105 MPH 12H 30/1800Z 30.6N 57.1W 90 KT 105 MPH 24H 31/0600Z 34.0N 54.3W 85 KT 100 MPH 36H 31/1800Z 38.5N 50.5W 80 KT 90 MPH 48H 01/0600Z 43.5N 46.7W 65 KT 75 MPH...POST-TROP/EXTRATROP 72H 02/0600Z 50.5N 35.5W 55 KT 65 MPH...POST-TROP/EXTRATROP 96H 03/0600Z 57.5N 21.5W 50 KT 60 MPH...POST-TROP/EXTRATROP 120H 04/0600Z 63.0N 9.0W 45 KT 50 MPH...POST-TROP/EXTRATROP $$ Forecaster Pasch |