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| #1240636 (Received by flhurricane at: 4:48 AM 07.Aug.2025) TCDAT4 Tropical Storm Dexter Discussion Number 14 NWS National Hurricane Center Miami FL AL042025 500 AM AST Thu Aug 07 2025 Dexter is on the edge of being extratropical. An earlier scatterometer overpass showed what is likely a warm front extending from the east into or near the center. In addition, a cloud band in the southeastern semicircle appears to be a developing cold front. However, a strong convective burst is currently occurring a little east of the center, and based on this Dexter as maintained as a tropical storm at this time. Satellite intensity estimates have changed little since the last advisory, so the initial intensity is held at 45 kt. Dexter should complete extratropical transition during the next 6-12 h as it merges with a mid- to upper-level trough approaching from the northwest. Global model show strengthening due to baroclinic forcing as this happens, and Dexter is forecast to become a hurricane-force extratropical low in about 24 hours. Gradual weakening is expected after that time as the upper-level trough dampens out. The NHC intensity forecast remains above the guidance in the short term, but in line with the bulk of the models from 48 to 96 hours. The cyclone is forecast to weaken to a trough by 120 h. The initial motion is now 070/16. A northeastward motion is expected during the next day or two as Dexter interacts and merges with the aforementioned trough. After that time, a turn back to the east-northeast or east is likely as the cyclone is steered by the mid-latitude westerly flow. The guidance nudged slightly northward between 24-60 h, and the new track forecast has a similar small nudge. It is otherwise similar to the previous forecast and close to the various consensus models. FORECAST POSITIONS AND MAX WINDS INIT 07/0900Z 40.6N 52.1W 45 KT 50 MPH 12H 07/1800Z 41.7N 49.0W 55 KT 65 MPH...POST-TROP/EXTRATROP 24H 08/0600Z 43.4N 45.3W 65 KT 75 MPH...POST-TROP/EXTRATROP 36H 08/1800Z 44.8N 41.2W 60 KT 70 MPH...POST-TROP/EXTRATROP 48H 09/0600Z 45.7N 36.8W 50 KT 60 MPH...POST-TROP/EXTRATROP 60H 09/1800Z 46.3N 32.4W 40 KT 45 MPH...POST-TROP/EXTRATROP 72H 10/0600Z 46.7N 28.5W 35 KT 40 MPH...POST-TROP/EXTRATROP 96H 11/0600Z 47.6N 20.7W 30 KT 35 MPH...POST-TROP/EXTRATROP 120H 12/0600Z...DISSIPATED $$ Forecaster Beven |
