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| #1283106 (Received by flhurricane at: 4:51 PM 21.Oct.2026) TCDAT5 Subtropical Storm Josephine Discussion Number 1 NWS National Hurricane Center Miami FL AL102026 500 PM AST Wed Oct 21 2026 The non-tropical area of low pressure (Invest AL93) that we have been monitoring this week has acquired enough subtropical characteristics to be considered a subtropical storm. Scatterometer data showed that fronts near the cyclone had dissipated, with a smaller radius-of-maximum wind than yesterday. Additionally moderate-to-deep convection has been organizing near and west of the warm-core center. Thus, advisories have been initiated on a subtropical storm, and 55 kt is shown as the initial intensity based on the scatterometer data. Josephine has been moving slowly northward today as a shortwave ridge passes across the northeastern United States. The storm should accelerate northeastward tomorrow as a mid-latitude trough digs into the Great Lakes and Northeastern United States, taking the system away from the US. By Friday, the low should turn eastward, to the south of Newfoundland. Model guidance is in good agreement on this path, and the new forecast is close to a blend of the global model consensus and the NOAA corrected-consensus aid HCCA. The subtropical storm will likely intensify during the next day or so through a favorable trough interaction while it remains near the north wall of the Gulf Stream. Global models are in good agreement on a band of hurricane-force winds developing tomorrow on the back side of the low as it undergoes extratropical transition. A slow weakening is anticipated by late Friday with the loss of forcing from the trough while the system moves over cold water. The NHC intensity forecast is similar to a blend of the GFS/ECMWF global model solutions. The cyclone should become absorbed in about 4 days within a much larger low over the North Atlantic. 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, and the system is forecast to move away from the coast, those products will remain in effect until the threat diminishes. FORECAST POSITIONS AND MAX WINDS INIT 21/2100Z 37.4N 69.5W 55 KT 65 MPH...SUBTROPICAL 12H 22/0600Z 38.1N 69.0W 60 KT 70 MPH...SUBTROPICAL 24H 22/1800Z 39.6N 66.2W 65 KT 75 MPH...POST-TROP/EXTRATROP 36H 23/0600Z 41.4N 61.6W 70 KT 80 MPH...POST-TROP/EXTRATROP 48H 23/1800Z 43.3N 56.9W 60 KT 70 MPH...POST-TROP/EXTRATROP 60H 24/0600Z 44.1N 53.5W 50 KT 60 MPH...POST-TROP/EXTRATROP 72H 24/1800Z 44.4N 50.4W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 25/1800Z 43.5N 37.5W 40 KT 45 MPH...POST-TROP/EXTRATROP 120H 26/1800Z...DISSIPATED $$ Forecaster Blake |
