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| #1246657 (Received by flhurricane at: 10:57 AM 30.Sep.2025) TCDAT4 Hurricane Imelda Discussion Number 16 NWS National Hurricane Center Miami FL AL092025 1100 AM EDT Tue Sep 30 2025 Imelda is gradually becoming better organized, with deep convection increasing near the center and banding features becoming more evident. An Air Force Hurricane Hunter aircraft measured flight-level winds that supported hurricane strength, although the central pressure has not yet fallen very much. The current intensity is set, perhaps conservatively, at 70 kt. Imelda is moving northeastward, or around 040/6 kt. A mid-level trough near the U.S. east coast should cause the hurricane to accelerate east-northeastward during the next couple of days. This track will bring the center of the hurricane near Bermuda in 36 hours or so. The official forecast is a bit south of the latest simple and corrected dynamical model consensus predictions, perhaps reflecting some binary interaction with the circulation of Humberto as the pair of tropical cyclones get closer together. The hurricane is embedded in an environment of moderate south-southwesterly vertical wind shear, but will be moving over warm waters and within a moist low- to mid-level air mass. Moreover, upper-level divergence associated a trough to the northwest of Imelda is likely to produce some positive forcing for intensification during the next day or so. So the system is likely to be rather potent while it passes near Bermuda. Later in the forecast period, the global models show the system merging with a broad baroclinic zone over the north Atlantic. The official intensity forecast is similar to the latest correct consensus model solution. KEY MESSAGES: 1. Imelda is expected bring damaging hurricane-force-winds to Bermuda when it passed near or over that island by Wednesday afternoon or evening. A Hurricane Warning is now in effect for Bermuda. 2. Imelda is likely to cause large and damaging waves in Bermuda. 3. Heavy rainfall could cause flash flooding across Bermuda Wednesday into Thursday. 4. Swells and high surf from both Humberto and Imelda are expected to produce dangerous marine conditions and rip currents along much of the East Coast of the United States during the next several days. FORECAST POSITIONS AND MAX WINDS INIT 30/1500Z 29.1N 76.6W 70 KT 80 MPH 12H 01/0000Z 29.8N 74.6W 75 KT 85 MPH 24H 01/1200Z 31.0N 71.0W 80 KT 90 MPH 36H 02/0000Z 32.6N 65.2W 85 KT 100 MPH 48H 02/1200Z 34.3N 60.0W 80 KT 90 MPH 60H 03/0000Z 36.7N 53.9W 75 KT 85 MPH...POST-TROPICAL 72H 03/1200Z 39.3N 50.4W 60 KT 70 MPH...POST-TROP/EXTRATROP 96H 04/1200Z 43.6N 46.4W 50 KT 60 MPH...POST-TROP/EXTRATROP 120H 05/1200Z 50.5N 37.0W 40 KT 45 MPH...POST-TROP/EXTRATROP $$ Forecaster Pasch |
