Issued at 500 PM AST Tue Sep 23 2025
000 WTNT42 KNHC 232041 TCDAT2 Hurricane Gabrielle Discussion Number 28 NWS National Hurricane Center Miami FL AL072025 500 PM AST Tue Sep 23 2025 This afternoon, Gabrielle's presentation on satellite imagery is starting to degrade a bit, with the clear eye observed this morning becoming more cloud filled. In addition, the vertical tilt appears to be gradually increasing, and a recent 1724 UTC AMSR2 microwave pass also shows that the eyewall is also becoming more eroded on the southwest side, likely due to increasing shear. Both the SAB and TAFB 18 UTC Dvorak fixes were still CI T6.0/115 kt, and the objective intensity estimates range from 107 to 122 kt, so the initial intensity was only nudged down to 115 kt on this advisory. The hurricane is gradually accelerating to the east-northeast, with the estimated motion at 065/18 kt. This general motion should continue for the next 2-3 days with some further acceleration as it rounds the edge of the subtropical ridge centered to its southwest. Another upper-level trough approaches Gabrielle in 2-3 days, and should result in the hurricane turning back a little more poleward in 72 h, with Gabrielle moving through the Azores in 48-60 h. Compared to this morning, the guidance has made another southward shift, and the NHC track forecast was moved a little south of the prior advisory, but not as far south as the HCCA and TVCN consensus aids. Further southward adjustments may be necessary in subsequent forecast cycles. Vertical wind shear continues to slowly increase over the hurricane, now diagnosed at 20 kt by the ECMWF-based SHIPS. This shear will increase further while Gabrielle moves over cooler ocean waters, and the latest guidance shows a slightly faster rate of weakening than earlier. The NHC intensity forecast follows suit, showing steady weakening through the next 2-3 days, though Gabrielle should still be a hurricane when it moves across the Azores. Thereafter, a trough interaction will hasten the extratropical transition of the hurricane, which should be complete in about three days. The resulting baroclinic interaction may temporarily slow the weakening rate between 48-72 hours, but more steady weakening should resume after Gabrielle becomes post-tropical. The NHC intensity guidance is in good agreement with the guidance suite, a little lower than the prior cycle. KEY MESSAGES: 1. Gabrielle is forecast to approach the Azores late on Thursday as a hurricane. A Hurricane Watch remains in effect for all of the islands of the Azores, and interests there should closely monitor Gabrielle's progress as hurricane conditions are possible later this week. 2. Swells generated by Gabrielle will continue to affect Bermuda, the east coast of the United States from North Carolina northward and Atlantic Canada during the next couple of days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. FORECAST POSITIONS AND MAX WINDS INIT 23/2100Z 34.6N 56.2W 115 KT 130 MPH 12H 24/0600Z 35.2N 52.7W 105 KT 120 MPH 24H 24/1800Z 35.8N 47.0W 95 KT 110 MPH 36H 25/0600Z 36.3N 40.8W 85 KT 100 MPH 48H 25/1800Z 37.4N 34.6W 75 KT 85 MPH 60H 26/0600Z 39.5N 28.0W 70 KT 80 MPH 72H 26/1800Z 41.1N 23.5W 60 KT 70 MPH...POST-TROP/EXTRATROP 96H 27/1800Z 42.7N 15.5W 45 KT 50 MPH...POST-TROP/EXTRATROP 120H 28/1800Z 40.4N 10.0W 35 KT 40 MPH...POST-TROP/EXTRATROP $$ Forecaster Papin
NHC Atlantic
