Issued at 1100 PM AST Wed Aug 06 2025
174 WTNT44 KNHC 070238 TCDAT4 Tropical Storm Dexter Discussion Number 13 NWS National Hurricane Center Miami FL AL042025 1100 PM AST Wed Aug 06 2025 Dexter is very close to being an extratropical cyclone. Satellite images suggest that frontal features are forming both to the east and south of the center, and the overall cloud pattern is beginning to take on an extratropical appearance. Strong westerly vertical wind shear has caused the low-level center to become completely exposed with disorganized convection limited to the northeast quadrant. The initial intensity is held at 45 kt, which is in line with the latest satellite intensity estimates and recent ASCAT data. A mid- to upper-level trough currently over the Canadian Maritimes is expected to merge with the system early Thursday, which should complete Dexter's extratropical transition. This will also likely cause strengthening due to baroclinic forcing, and Dexter could 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 is slightly above the guidance in the short term, but in line with the bulk of the models from 48 to 96 hours. Dexter is moving a little faster to the east now, with the latest initial motion estimated to be 085/14 kt. 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 predicted in the mid-latitude westerly flow. The NHC track forecast lies fairly close to the various consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 07/0300Z 40.2N 54.2W 45 KT 50 MPH 12H 07/1200Z 40.9N 51.1W 55 KT 65 MPH...POST-TROP/EXTRATROP 24H 08/0000Z 42.6N 46.7W 65 KT 75 MPH...POST-TROP/EXTRATROP 36H 08/1200Z 44.3N 43.0W 60 KT 70 MPH...POST-TROP/EXTRATROP 48H 09/0000Z 45.3N 38.5W 50 KT 60 MPH...POST-TROP/EXTRATROP 60H 09/1200Z 46.0N 34.4W 40 KT 45 MPH...POST-TROP/EXTRATROP 72H 10/0000Z 46.7N 29.7W 35 KT 40 MPH...POST-TROP/EXTRATROP 96H 11/0000Z 47.4N 22.0W 30 KT 35 MPH...POST-TROP/EXTRATROP 120H 12/0000Z...DISSIPATED $$ Forecaster Cangialosi