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| #1246294 (Received by flhurricane at: 4:57 PM 27.Sep.2025) TCDAT3 Hurricane Humberto Discussion Number 13 NWS National Hurricane Center Miami FL AL082025 500 PM AST Sat Sep 27 2025 Humberto has quickly strengthened during the past several hours. A very symmetric ring of cloud tops colder than -70 deg C now surrounds the clear eye of the hurricane. At 1800 UTC, the TAFB subjective Dvorak analysis was 7.0/140 kt. Most of the objective techniques like the UW-CIMSS ADT and AIDT, as well as the SAB subjective Dvorak fix supported a slightly lower intensity, closer to 130 kt. However, since that time, cloud tops around Humberto have gotten colder and the objective estimates have increased. Therefore, the intensity has been set at 140 kt, making Humberto the second category 5 hurricane of the 2025 Atlantic hurricane season. Some additional strengthening is possible tonight. Internal factors like eyewall replacement cycles will likely dominate Humberto`s intensity for the next day or two, so fluctuations in maximum wind speeds are expected. All of the intensity guidance indicates that some slow weakening is expected to begin by Monday, before Humberto begins to interact with a mid-latitude trough on Tuesday. The cyclone should then begin its extratropical transition shortly thereafter, resulting in a quicker decrease in maximum winds but an expansion of the overall wind field. Overall, little change was needed to the official forecast aside from showing a higher intensity for the first day or two. Only a slight westward adjustment was made to the track forecast. Humberto is moving slightly faster, but westward, near 9 kt. The hurricane is still forecast to move around the subtropical ridge for the next few days before it interacts with the aforementioned trough and accelerates quickly northeastward. The spread in the model track guidance has increased since the last advisory, particularly with regard to how fast Humberto will accelerate northeastward in 4 or 5 days. Confidence in that aspect of the forecast has therefore decreased, even though little change was made to the official forecast. The NHC forecast remains generally based on a blend of the GDMI, the AIGEFS and HCCA. FORECAST POSITIONS AND MAX WINDS INIT 27/2100Z 22.9N 61.1W 140 KT 160 MPH 12H 28/0600Z 23.5N 62.7W 145 KT 165 MPH 24H 28/1800Z 24.7N 64.6W 140 KT 160 MPH 36H 29/0600Z 26.2N 66.1W 135 KT 155 MPH 48H 29/1800Z 28.0N 67.5W 125 KT 145 MPH 60H 30/0600Z 30.0N 68.5W 115 KT 130 MPH 72H 30/1800Z 32.1N 68.5W 105 KT 120 MPH 96H 01/1800Z 36.1N 62.4W 95 KT 110 MPH 120H 02/1800Z 42.5N 46.5W 85 KT 100 MPH...POST-TROP/EXTRATROP $$ Forecaster D. Zelinsky/Bookbinder |
