Tropical Cyclone Discussion
Issued by NWS
Issued by NWS
213 WTNT45 KNHC 140238 TCDAT5 Tropical Storm Erin Discussion Number 11 NWS National Hurricane Center Miami FL AL052025 1100 PM AST Wed Aug 13 2025 Satellite images show that a solid area of convection remains near Erin, with low-cloud motions suggesting the center is on the northeastern side of the thunderstorm activity. Overall, there hasn`t been a lot of change with the satellite presentation, and that is reflected in recent stable Dvorak and scatterometer values. The initial intensity is held at 45 kt for this advisory. The environment around Erin should remain marginally conducive during the next day or so, which will likely promote gradual strengthening. Thereafter, the storm is forecast to move across warmer waters, with potentially a decrease in shear. This evolution results in a period of potential rapid intensification late this week, and the official forecast reflects that possibility. While shear is generally forecast to increase over the weekend, this appears to be canceled out by large-scale divergence and water temperatures above 29C. Most models respond to this by showing a lower rate of intensification at that time. The new intensity forecast is adjusted upward somewhat from the previous forecast beyond 24 h based on the current guidance. There is increasing confidence on a large and powerful hurricane over the southwestern Atlantic Ocean this weekend. The initial motion is now 270/14 kt. There are no significant changes to the forecast track or steering. Erin should move westward overnight and then west-northwestward from Thursday through the weekend due to steering from the subtropical ridge. The ridge is forecast to break by early next week, resulting in a turn towards the northwest or north-northwest. The new forecast is basically an update of the previous forecast in the near term, and on the eastern side of the guidance envelope by day 5 between the consensus and the Google Deep Mind model. 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 14/0300Z 16.3N 46.6W 45 KT 50 MPH 12H 14/1200Z 16.5N 48.8W 50 KT 60 MPH 24H 15/0000Z 17.2N 51.8W 55 KT 65 MPH 36H 15/1200Z 18.0N 54.9W 70 KT 80 MPH 48H 16/0000Z 18.9N 57.8W 85 KT 100 MPH 60H 16/1200Z 19.8N 60.6W 95 KT 110 MPH 72H 17/0000Z 20.6N 62.9W 100 KT 115 MPH 96H 18/0000Z 22.8N 66.6W 105 KT 120 MPH 120H 19/0000Z 25.5N 68.5W 110 KT 125 MPH $$ Forecaster Blake