Issued at 500 AM AST Tue Sep 23 2025
000 WTNT42 KNHC 230849 TCDAT2 Hurricane Gabrielle Discussion Number 26 NWS National Hurricane Center Miami FL AL072025 500 AM AST Tue Sep 23 2025 Gabrielle remains an impressive hurricane in satellite imagery. However, it appears to have reached peak intensity, as the eyewall convective tops have become more asymmetric during the past few hours and the eye has become less distinct. This is likely due to the onset of moderate southwesterly vertical shear as shown by the restricted outflow in the southwestern quadrant. The various subjective and objective satellite intensity estimates are in the 115-125 kt range, so the initial intensity is held at 120 kt. The hurricane continues moving northeastward or 045/11 kt. Gabrielle should continue to move around the northwestern side of the mid-level subtropical ridge during the next 12-24 h and then accelerate east-northeastward in the southern portion of the mid-latitude westerlies. A slight turn to the northeast ahead of a higher-latitude trough is expected in 72-96 h, followed by a more eastward motion as Gabrielle merges with the trough. The guidance envelope has only minor changes since the last advisory. So, the new forecast, which lies near or just north of the consensus models, is close to the previous forecast through 60 h and a little south of it after that time. The new forecast is also a little faster than the previous forecast. Gradual weakening is expected during the next 24 h due to shear and gradually decreasing sea surface temperatures along the forecast track. After that, increasing shear and even cooler water should cause a faster weakening. While the above-mentioned trough could provide enhanced divergence aloft which could help Gabrielle maintain some of its intensity, it is also likely to cause Gabrielle to start extratropical transition in about 60 h. This transition will likely be complete just after the cyclone passes the Azores. The new intensity forecast is nudged downward from the previous forecast and is in good agreement with the intensity consensus. KEY MESSAGES: 1. Swells generated by Gabrielle will continue to affect Bermuda, the east coast of the United States from North Carolina northward, as well as 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. 2. Gabrielle is forecast to approach the Azores late on Thursday. Interests in the Azores should monitor the progress of Gabrielle though it is too soon to specify the magnitude of potential wind, rainfall, and wave impacts. FORECAST POSITIONS AND MAX WINDS INIT 23/0900Z 33.2N 59.7W 120 KT 140 MPH 12H 23/1800Z 34.2N 57.3W 115 KT 130 MPH 24H 24/0600Z 35.2N 52.7W 110 KT 125 MPH 36H 24/1800Z 35.8N 47.0W 100 KT 115 MPH 48H 25/0600Z 36.3N 40.7W 90 KT 105 MPH 60H 25/1800Z 37.9N 34.0W 80 KT 90 MPH 72H 26/0600Z 39.7N 28.5W 70 KT 80 MPH 96H 27/0600Z 43.3N 19.8W 55 KT 65 MPH...POST-TROP/EXTRATROP 120H 28/0600Z 42.7N 13.2W 40 KT 45 MPH...POST-TROP/EXTRATROP $$ Forecaster Beven
