Issued at 1100 PM AST Sun Sep 28 2025
855 WTNT43 KNHC 290243 TCDAT3 Hurricane Humberto Discussion Number 18 NWS National Hurricane Center Miami FL AL082025 1100 PM AST Sun Sep 28 2025 Humberto remains a powerful category 4 hurricane over the subtropical western Atlantic. The Air Force Hurricane Hunters have been investigating Humberto this evening and found that the major hurricane has concentric eyewalls, with a double wind maximum noted in all quadrants. Based on the flight-level wind data, the initial intensity is set at 120 kt. Dropsonde data from the aircraft suggest that the minimum pressure is quite low at 928 mb. Humberto is moving northwestward at 12 kt in the flow on the south-southwest side of a subtropical high. The major hurricane is expected to gradually turn to the north by late Monday and Tuesday as the high shifts to the east and weakens. After that, a trough is expected to amplify over the north Atlantic, and that should cause Humberto to turn sharply and accelerate east-northeastward Tuesday night and Wednesday. The models are in good agreement, and only minor changes were made to the previous track forecast. While there is high confidence that the core of Humberto will miss Bermuda, there is a possibility of tropical-storm-force winds occurring there late Tuesday and Wednesday in Humberto's outer bands. The intensity of Humberto will likely fluctuate over the next 12 to 24 hours, but gradual weakening is expected after that due to increasing shear and decreasing SSTs. Extratropical transition is now forecast to be complete by 72 hours when the system is expected to merge with the aforementioned mid- to upper-level trough and develop frontal features. The NHC intensity forecast is near the middle of the guidance envelope. The hurricane is expected to grow in size as it gains latitude during the next few days, which will result in a large area of rough seas. See Key Messages below for more information. KEY MESSAGES: 1. Tropical-storm-force winds could begin to affect Bermuda by late Tuesday, and a tropical storm watch is in effect for the island. Interests there should continue to monitor the progress of Humberto. 2. Dangerous marine conditions, including high surf and life-threatening rip currents, are affecting beaches of the northern Caribbean, Bahamas, and Bermuda. The dangerous surf conditions are expected to begin affecting much of the east coast of the U.S. on Monday. FORECAST POSITIONS AND MAX WINDS INIT 29/0300Z 26.2N 66.2W 120 KT 140 MPH 12H 29/1200Z 27.5N 67.3W 120 KT 140 MPH 24H 30/0000Z 29.5N 68.5W 115 KT 130 MPH 36H 30/1200Z 31.9N 68.9W 105 KT 120 MPH 48H 01/0000Z 34.2N 68.0W 95 KT 110 MPH 60H 01/1200Z 35.9N 64.8W 90 KT 105 MPH 72H 02/0000Z 37.3N 58.7W 85 KT 100 MPH...POST-TROP/EXTRATROP 96H 03/0000Z 43.5N 41.5W 75 KT 85 MPH...POST-TROP/EXTRATROP 120H 04/0000Z...DISSIPATED $$ Forecaster Cangialosi
NHC Atlantic
