613 WTNT43 KNHC 301433 TCDAT3 Tropical Storm Leslie Discussion Number 17 NWS National Hurricane Center Miami FL AL132018 1100 AM AST Sun Sep 30 2018 Deep convection has increased a little during the past several hours in a band to the southeast of the center, but the shower activity remains quite limited elsewhere in the circulation. The latest satellite intensity estimates and a recent ASCAT pass still support an initial intensity of 45 kt. Leslie is expected to be moving into a lower wind shear environment and over warmer SSTs during the next few days. These conditions should support some gradual strengthening during that time period. After that time, however, Leslie is expected to move over cooler waters, partly induced by its own upwelling, as it heads northeastward back over its previous track. Accordingly, slight weakening is shown toward the end of the forecast period. The NHC intensity forecast is similar to the previous one and generally follows the consensus models, IVCN and HCCA. Leslie is drifting to the southwest, with the latest initial motion estimate being 230/3 kt. Leslie is caught in very weak steering currents, and a continued slow southwest to south motion is expected during the next few days. Thereafter, the models show a weak trough developing to the southwest of Leslie and that should cause the system to move northeastward at a slightly faster pace. The models have trended a little to the east this cycle, and the NHC forecast has been adjusted in that direction. The bottom line is that Leslie is forecast to meander over the central Atlantic through the forecast period. Large swells generated by Leslie when it was a strong extratropical low will continue to affect Bermuda, the east coast of the United States, and most of the Greater and Lesser Antilles for another day or two. These swells could cause life-threatening surf and rip currents. Although the swells will diminish some by mid-week, they will likely remain hazardous for the same locations through the forecast period due to Leslie's slow motion. The initial 34-kt wind radii were adjusted based on a 1257 UTC ASCAT pass. FORECAST POSITIONS AND MAX WINDS INIT 30/1500Z 33.6N 52.6W 45 KT 50 MPH 12H 01/0000Z 33.2N 53.1W 50 KT 60 MPH 24H 01/1200Z 32.9N 53.6W 55 KT 65 MPH 36H 02/0000Z 32.3N 54.0W 55 KT 65 MPH 48H 02/1200Z 31.6N 54.3W 60 KT 70 MPH 72H 03/1200Z 30.8N 54.2W 65 KT 75 MPH 96H 04/1200Z 33.0N 52.5W 65 KT 75 MPH 120H 05/1200Z 36.0N 51.5W 60 KT 70 MPH $$ Forecaster Cangialosi