Issued at 500 PM AST Thu Sep 18 2025
560 WTNT42 KNHC 182053 TCDAT2 Tropical Storm Gabrielle Discussion Number 7 NWS National Hurricane Center Miami FL AL072025 Issued by the NWS Weather Prediction Center College Park MD 500 PM AST Thu Sep 18 2025 Gabrielle continues to fight off strong westerly vertical wind shear and significant dry air entrainment this afternoon. Some thunderstorms have blossomed on the storm's eastern flank, which is an improvement from its naked low-level swirl earlier this morning. The initial intensity is held at 45 kt based on recent scatterometer data of at least 40 kt and little in the way of change to its structure from earlier this morning. Atmospheric conditions are expected to remain hostile for another day or so, meaning Gabrielle is likely maintain its current intensity or weaken slightly during that time. Recent 12Z guidance indicates vertical wind shear relaxes and an increasingly moist vertical profile should foster a much improved environment for strengthening this weekend, with the GFS model trending toward the more conducive ECMWF solution. As a result, intensity guidance is notable higher on this cycle. The NHC intensity forecast is raised from the previous one, but not as high as the model consensus mostly due to continuity. There are a growing number of hurricane models that are indicating Gabrielle could approach major hurricane strength after the weekend. Gabrielle is moving west-northwestward at 13 kt and should maintain this track with a bend toward the northwest over the next few days as the storm is steered primarily by a subtropical ridge over the central Atlantic. A turn toward the north and northeast is forecast to occur late this weekend and early next week when Gabrielle rounds the western periphery of the ridge and a frontal system approaches from the west. While the guidance envelope has shrunk on this forecast cycle, there are some significant speed differences, with the ECMWF/GFS models considerably faster than the Google Deep Mind ensemble. Although no significant changes to the forecast were made, confidence remains on the lower side given the along-track model spread and an unclear intensity forecast beyond 48 hours. Interests in Bermuda should continue to monitor Gabrielle over the next several days. FORECAST POSITIONS AND MAX WINDS INIT 18/2100Z 20.8N 52.7W 45 KT 50 MPH 12H 19/0600Z 21.5N 54.2W 40 KT 45 MPH 24H 19/1800Z 22.6N 56.3W 40 KT 45 MPH 36H 20/0600Z 23.9N 58.1W 45 KT 50 MPH 48H 20/1800Z 25.3N 59.8W 50 KT 60 MPH 60H 21/0600Z 27.1N 61.1W 55 KT 65 MPH 72H 21/1800Z 29.0N 62.0W 65 KT 75 MPH 96H 22/1800Z 33.0N 61.0W 85 KT 100 MPH 120H 23/1800Z 39.0N 52.5W 80 KT 90 MPH $$ Forecaster Mullinax/Blake
