Show Selection: |
#943484 (Received by flhurricane at: 11:11 AM 08.Oct.2018) TCDAT3 Tropical Storm Leslie Discussion Number 49 NWS National Hurricane Center Miami FL AL132018 1100 AM AST Mon Oct 08 2018 For the fourth (and hopefully final) time as a tropical or subtropical cyclone, Leslie has crossed 48W. The convective pattern of the tropical storm hasn`t changed significantly over the past several hours, though there is some evidence of a convective band attempting to wrap around the western side of the storm. The initial intensity is still 45 kt, based on a blend of the most recent current intensity estimates from TAFB, SAB, and the UW-CIMSS SATCON. There has been little change in the intensity forecast. Just about all of the typically reliable intensity models still call for Leslie to gradually strengthen over the next 3 days, despite marginal SSTs. All of the dynamical models call for Leslie to become a hurricane once again by 72 h, but SHIPS and LGEM are a little lower. The official intensity forecast remains near the HCCA and IVCN consensus aids, and calls for Leslie to become a hurricane by the end of the week. Leslie has continued to move east-southeastward, now at 12 kt, and the global models are in good agreement that this motion will continue through today. After that time, most of the guidance generally shows that Leslie will separate from a mid-latitude trough, causing the tropical storm to turn toward the southeast or south-southeast and slow down. A day or so after that, another mid-latitude trough will approach from the west and cause Leslie to accelerate toward the east-northeast. The timing of Leslie`s acceleration is still very uncertain, and the model spread beyond 72 h remains very high. Until the spread decreases, I don`t feel confident making a big change to the forecast, so the official track forecast has only been slightly tweaked to bring it closer to HCCA and TVCN. FORECAST POSITIONS AND MAX WINDS INIT 08/1500Z 34.6N 47.0W 45 KT 50 MPH 12H 09/0000Z 33.6N 45.2W 50 KT 60 MPH 24H 09/1200Z 32.0N 43.5W 50 KT 60 MPH 36H 10/0000Z 30.2N 42.2W 55 KT 65 MPH 48H 10/1200Z 29.1N 41.2W 60 KT 70 MPH 72H 11/1200Z 29.5N 37.0W 65 KT 75 MPH 96H 12/1200Z 33.0N 28.0W 70 KT 80 MPH 120H 13/1200Z 39.0N 18.0W 65 KT 75 MPH $$ Forecaster Zelinsky |