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#943571 (Received by flhurricane at: 10:42 PM 08.Oct.2018) TCDAT3 Tropical Storm Leslie Discussion Number 51 NWS National Hurricane Center Miami FL AL132018 1100 PM AST Mon Oct 08 2018 Satellite and microwave data show that Leslie continues to have a small central dense overcast, with the latest microwave images suggesting that Leslie is forming a mid-level eye. Although deep convection has recently decreased somewhat, all of the 00Z intensity estimates were 55 kt or higher, so the wind speed is set to that value. There is no significant change in initial motion- still southeastward at about 12 kt. Leslie should slow down and turn toward the south-southeast during the next day or two as the cyclone becomes steered by a mid-level ridge over the central Atlantic. A new trough moves into the eastern Atlantic after that time, which should eject Leslie generally east-northeastward to the south of the Azores. Models continue to be in poor agreement on whether that trough will accelerate Leslie quickly to the northeast at long range or drop the cyclone to the southwest of Portugal. The recent GFS-based guidance has generally shifted southward and is slower, more in line with the 12Z UK/ECMWF models. The new NHC forecast follows that trend, but is still on the northern side of the consensus due to continuity concerns, and additional southward adjustments could be required on later advisories. Leslie is forecast to move across marginally warm waters within a moderate shear but a more moist environment over the next few days. These conditions are likely to support slow strengthening, and model guidance is in general agreement on this scenario. Only minor adjustments were made to the previous forecast, and the NHC forecast remains between the intensity consensus and corrected- consensus aids. By day 5, increasing shear and cold waters should weaken Leslie, and it will probably lose convection to transition into a post-tropical cyclone. FORECAST POSITIONS AND MAX WINDS INIT 09/0300Z 32.9N 44.6W 55 KT 65 MPH 12H 09/1200Z 31.5N 43.3W 55 KT 65 MPH 24H 10/0000Z 29.6N 42.5W 60 KT 70 MPH 36H 10/1200Z 28.1N 42.1W 60 KT 70 MPH 48H 11/0000Z 27.9N 41.2W 65 KT 75 MPH 72H 12/0000Z 30.0N 35.5W 75 KT 85 MPH 96H 13/0000Z 33.5N 24.5W 70 KT 80 MPH 120H 14/0000Z 35.5N 16.0W 55 KT 65 MPH...POST-TROPICAL $$ Forecaster Blake |