Issued at 500 PM AST Sun Sep 28 2025
000 WTNT43 KNHC 282039 TCDAT3 Hurricane Humberto Discussion Number 17 NWS National Hurricane Center Miami FL AL082025 500 PM AST Sun Sep 28 2025 Humberto continues to have a small inner core, surrounded by a much larger ring of deep convection. This structure is evident in visible and IR satellite imagery, in which a moat of warmer cloud tops outside of the inner eyewall has been noted at times during day. This structure has likely caused Humberto's intensity to decrease today, and the 125-kt intensity estimate is on the high end of recent objective and subjective estimates. However, this has also caused the wind field to increase, which was confirmed by ASCAT data that arrived shortly after the issuance of the previous advisory. An Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate Humberto this evening, which should provide more information about the strength and structure of the hurricane. Overall, no significant changes were made to the NHC track, intensity, or radii forecasts for Humberto. The hurricane should move west and then north of Bermuda over the next few days while it slowly weakens but grows in size. Confidence in the forecast through that period is fairly high, with the model spread being smaller than normal. The forecast uncertainty is higher after that, but Humberto is subsequently expected to become a post-tropical frontal low between 72 and 96 h. Regardless of its exact strength or forward speed, Humberto will be a strong and large hurricane-strength low throughout the forecast period, even as its surface circulation will likely become ill defined by the end of the week. The NHC forecast is close to a blend of the multi-model consensus and the Google DeepMind Ensemble Mean at all times. The primary concerns for Humberto continue to be its production of dangerous surf which will affect Bermuda and the U.S. East Coast for the next several days, and the growth of its wind field, which could result in tropical-storm-force winds affecting Bermuda by late Tuesday. KEY MESSAGES: 1. Tropical-storm-force winds could begin to affect Bermuda by late Tuesday. The Bermuda Weather Service has issued a Tropical Storm Watch for Bermuda. 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 the U.S. East Coast on Monday. FORECAST POSITIONS AND MAX WINDS INIT 28/2100Z 25.5N 65.4W 125 KT 145 MPH 12H 29/0600Z 26.8N 66.6W 120 KT 140 MPH 24H 29/1800Z 28.7N 67.9W 115 KT 130 MPH 36H 30/0600Z 30.8N 68.8W 105 KT 120 MPH 48H 30/1800Z 33.3N 68.7W 95 KT 110 MPH 60H 01/0600Z 35.2N 67.1W 90 KT 105 MPH 72H 01/1800Z 36.4N 62.9W 85 KT 100 MPH 96H 02/1800Z 41.5N 47.0W 80 KT 90 MPH...POST-TROP/EXTRATROP 120H 03/1800Z...DISSIPATED $$ Forecaster D. Zelinsky
NHC Atlantic
