Issued at 500 AM AST Thu Aug 14 2025
403 WTNT45 KNHC 140846 TCDAT5 Tropical Storm Erin Discussion Number 12 NWS National Hurricane Center Miami FL AL052025 500 AM AST Thu Aug 14 2025 Satellite imagery shows that Erin continues to produce an area of deep convection, with the center estimated to be on the northeastern side of the convective shield. There has not been much change since the previous advisory, and there has been no recent microwave imagery to assess the overall structure. However, TAFB noted a slight increase in the curved banding with the latest data-t value. Subjective satellite current intensity estimates have held steady around 45 kt, and objective satellite estimates from UW-CIMSS range from 39 to 51 knots, with a satellite consensus of 46 kt. Using a blend of these estimates, the intensity is held at 45 kt for this advisory. The overall environment around Erin is conducive for gradual strengthening during the next day or so. Thereafter, the system is forecast to move across warmer waters, and the GFS and EC SHIPS guidance suggests a slight decrease in shear. This increasingly favorable environment could result in a period of rapid intensification, which is explicitly forecast between 24-48 h. Wind shear may slightly increase later this weekend, although sea surface temperatures remain around 29C, with favorable divergence aloft. Most of the intensity guidance continues to show strengthening at this time frame just at a steady rate, with Erin forecast to become a major hurricane by day 3. The NHC intensity forecast is similar to the previous and lies closest to the HCCA corrected consensus, there are some models, such as the FSSE, that depict a higher intensity by the end of the forecast period than the current NHC forecast. There continues to be confidence that Erin will be a large and powerful hurricane over the southwestern Atlantic Ocean this weekend. Erin continues to move westward at an estimated motion of 270/15 kt. The storm is being steered by a subtropical ridge to the north, and the system should gradually turn more west-northwestward later tonight, with this motion anticipated into the weekend. A weakness in the ridge is forecast to develop early next week, resulting in a turn towards the northwest or north-northwest. The guidance is fairly tightly cluster through day 3, with some slight along-track spread on the turn toward the northwest. Beyond day 3, the GFS and Google DeepMind are on the eastern edge of the guidance, and the hurricane regional models on the western side. The latest NHC forecast is similar to the previous and lies near the consensus aids. There is still a greater than normal uncertainty about what impacts Erin may bring to portions of the Bahamas, the east coast of the United States, and Bermuda in the long range. KEY MESSAGES: 1. Locally heavy rainfall, high surf and rip currents, and tropical-storm force winds could occur in portions of the northern Leeward Islands, the Virgin Islands, and Puerto Rico this weekend as the core of Erin passes north of those islands. Interests in these areas should continue to monitor the progress of Erin. 2. While there is still uncertainty in what impacts might occur in portions of the Bahamas, the east coast of the United States, and Bermuda next week, the risk of dangerous surf and rip currents across the western Atlantic basin next week is increasing. As we approach the climatological peak of the hurricane season, this is an opportune time to ensure your preparedness plans are in place. FORECAST POSITIONS AND MAX WINDS INIT 14/0900Z 16.3N 48.2W 45 KT 50 MPH 12H 14/1800Z 16.8N 50.5W 50 KT 60 MPH 24H 15/0600Z 17.6N 53.5W 55 KT 65 MPH 36H 15/1800Z 18.5N 56.5W 70 KT 80 MPH 48H 16/0600Z 19.3N 59.4W 85 KT 100 MPH 60H 16/1800Z 20.1N 62.0W 95 KT 110 MPH 72H 17/0600Z 21.0N 64.1W 100 KT 115 MPH 96H 18/0600Z 23.2N 67.3W 105 KT 120 MPH 120H 19/0600Z 26.0N 69.3W 110 KT 125 MPH $$ Forecaster Kelly