Official Discussion issued by the National Hurricane Center
Leslie (AL132024) DATA RELEASED: 10/12/2024 9:00:00 AM UTC
Copy of official data Tropical Storm Leslie Discussion Number 40 NWS National Hurricane Center Miami FL AL132024 500 AM AST Sat Oct 12 2024 Leslie has held steady through the night. The storm has maintained a small burst of deep convection near the low-level center, with cold cloud top temperatures of less than -80 degrees C. While the satellite intensity estimates have trended downward, the initial intensity is held at 45 kt in deference to the earlier scatterometer data. The storm is accelerating to the northeast at 21 kt in the flow ahead of an approaching deep-layer trough over the northwestern Atlantic. On Sunday, Leslie should turn east-northeastward to eastward and continue this motion through the remainder of the forecast period. Model guidance has shifted northward with a slight increase in forward speed this advisory cycle. The latest NHC forecast has been nudged northward and now lies between the previous prediction and on the southern side of the tightly clustered guidance envelope. Leslie, or its remnants, is now expected to move near or over the Azores late Sunday through early Monday. Leslie has a few more hours in a marginal environmental. Later today, deep-layer vertical wind shear is forecast to steadily increase and the storm is passing over the 26 degree C isotherm towards cooler waters. Global models suggest Leslie will lose its deep convection and merge with a frontal system in about a day. The official forecast now reflects the timing of this transition. It should be noted that while the models show a closed low pressure area through 72 h, the circulation could degenerate into an open trough before then due to the fast forward speed. FORECAST POSITIONS AND MAX WINDS INIT 12/0900Z 31.3N 45.9W 45 KT 50 MPH 12H 12/1800Z 33.8N 42.3W 45 KT 50 MPH 24H 13/0600Z 36.5N 36.6W 40 KT 45 MPH...POST-TROP/EXTRATROP 36H 13/1800Z 37.6N 31.0W 40 KT 45 MPH...POST-TROP/EXTRATROP 48H 14/0600Z 37.7N 25.5W 35 KT 40 MPH...POST-TROP/EXTRATROP 60H 14/1800Z 37.1N 21.0W 35 KT 40 MPH...POST-TROP/EXTRATROP 72H 15/0600Z 37.1N 16.4W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 16/0600Z...DISSIPATED $$ Forecaster Bucci |