Tropical Cyclone Discussion
219 WTNT45 KNHC 220256 TCDAT5 Subtropical Storm Josephine Discussion Number 2 NWS National Hurricane Center Miami FL AL102026 1100 PM AST Wed Oct 21 2026 Convection associated with Josephine has waned this evening. The latest satellite images show shallow to moderate convection in bands over the northern and western portions of the circulation. Despite its degraded satellite structure, partial scatterometer data show Josephine is still a powerful storm with a large radius of maximum wind and an asymmetric wind field. A band of 45-50 kt winds wraps around the northwest side of the system. Since the entire wind field was not sampled, the initial intensity is held at a possibly generous 55 kt for this advisory. Recent satellite fixes indicate Josephine is now moving slowly north-northeastward (015/5 kt). The storm is expected to accelerate to the northeast and east-northeast tomorrow as an upper-level trough amplifies over the Canadian Maritimes and the northeastern United States. Then, the low should become caught in mid-latitude westerlies and move eastward on Friday and into the weekend, with the center passing to the south of Newfoundland late Friday and Friday night. The track model guidance remains tightly clustered, and the NHC forecast is very similar to the previous one, generally falling between the corrected consensus (HCCA) and a simple average of the GFS/ECMWF models (GFEX). Josephine is unlikely to remain subtropical for long since the storm will encounter much cooler waters and stronger shear over the next 12-24 hours. However, the global models favor some near-term strengthening driven mostly by baroclinic processes and positive interaction with the approaching trough. This forecast shows Josephine becoming a hurricane-force, extratropical cyclone in 24 h, though it could lose subtropical characteristics even sooner. Gradual weakening is predicted beginning on Friday, and the updated forecast shows Josephine becoming absorbed by 96 h within a larger, extratropical low over the North Atlantic. Given the subtropical nature of this storm, the NHC intensity forecast continues to favor a blend of the GFS and ECMWF models. Since the coastal wind hazards with this system have been covered for the last several days through non-tropical products issued by local National Weather Service offices, these products will remain in effect until the threat diminishes and the system moves farther away from the U.S. coast. FORECAST POSITIONS AND MAX WINDS INIT 22/0300Z 37.7N 69.4W 55 KT 65 MPH...SUBTROPICAL 12H 22/1200Z 38.8N 67.9W 60 KT 70 MPH...SUBTROPICAL 24H 23/0000Z 40.3N 64.4W 65 KT 75 MPH...POST-TROP/EXTRATROP 36H 23/1200Z 42.2N 59.6W 65 KT 75 MPH...POST-TROP/EXTRATROP 48H 24/0000Z 43.5N 55.7W 55 KT 65 MPH...POST-TROP/EXTRATROP 60H 24/1200Z 44.1N 52.8W 50 KT 60 MPH...POST-TROP/EXTRATROP 72H 25/0000Z 44.1N 48.1W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 26/0000Z...DISSIPATED