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| #942278 (Received by flhurricane at: 4:48 AM 29.Sep.2018) TCDAT3 Subtropical Storm Leslie Discussion Number 12 NWS National Hurricane Center Miami FL AL132018 500 AM AST Sat Sep 29 2018 The deep convection has become more concentrated near the center during the past several hours indicating that Leslie is gradually acquiring some tropical characteristics, but the cyclone is still too attached to a complex deep-layer low. On this basis, Leslie is still considered a subtropical storm in this advisory with an initial intensity of 40 kt. Global models indicate that the subtropical cyclone will continue to be embedded within strong northerly shear during the next 2 days or so. After that time, the shear is forecast to relax and with a warm ocean along the cyclone`s path, Leslie is forecast to become fully tropical and reach hurricane status by the end of the forecast period. SHIPS model and its derivatives strengthen Leslie significantly, but the NHC forecast is a little less aggressive, and it follows the intensity consensus. Leslie has been moving toward the southwest or 230 degrees at 6 kt, steered by the flow around the western side of the large deep-layer low in which Leslie is embedded. Since this steering pattern is not expected to change, Leslie will probably continue on the same general track for the next 3 to 4 days. After that time, the large low weakens and the cyclone will become steered slowly northward by the flow ahead of an approaching mid-latitude trough. Nevertheless, Leslie is forecast to meander over the north-central Atlantic for several more days. This is the solution provided by most of the global models, and the NHC forecast follows very closely the multi-model consensus aids and the corrected consensus HCCA. Large swells previously generated by Leslie when it was a stronger extratropical low have already reached Bermuda, and will soon reach the Lesser and Greater Antilles. These swells are expected to reach portions of the east coast of the United States by Sunday. These swells could cause life-threatening surf and rip currents. FORECAST POSITIONS AND MAX WINDS INIT 29/0900Z 35.2N 50.3W 40 KT 45 MPH 12H 29/1800Z 34.4N 51.3W 45 KT 50 MPH 24H 30/0600Z 33.8N 52.2W 45 KT 50 MPH 36H 30/1800Z 33.5N 53.3W 50 KT 60 MPH 48H 01/0600Z 33.2N 54.0W 50 KT 60 MPH...TROPICAL CYCLONE 72H 02/0600Z 32.3N 55.0W 60 KT 70 MPH 96H 03/0600Z 31.0N 55.5W 65 KT 75 MPH 120H 04/0600Z 32.0N 56.0W 70 KT 80 MPH $$ Forecaster Avila |