Issued at 500 PM AST Thu Aug 14 2025
267 WTNT45 KNHC 142044 TCDAT5 Tropical Storm Erin Discussion Number 14 NWS National Hurricane Center Miami FL AL052025 500 PM AST Thu Aug 14 2025 Erin has changed little in organization during the past several hours. Conventional satellite imagery shows that the storm continues to produce strong convection near the center. However, a recently received AMSR2 overpass shows that the convection is confined mainly to the southwestern quadrant and lacks well-defined banding. Satellite intensity estimates are now in the 45-55 kt range, and the initial intensity remains 50 kt for this advisory. A NOAA Hurricane Hunter aircraft is en route investigate the system this evening, providing information on the storm's strength and structure. There is little change to either the intensity philosophy or forecast since the last advisory. Erin will be in an environment of light-to-moderate easterly vertical shear and moving over increasing sea surface temperatures during the next 48 h. These conditions should allow a faster rate of intensification during this time, and Erin is still forecast to become a hurricane by 24 h. The environment becomes less conducive after 48 h, with the global models forecasting northwesterly shear over the cyclone as a large upper-level anticyclone develops to the west. Despite this forecast shear, the global and regional hurricane models forecast intensification to continue, although at a slower rate than during the first 48 h. Based on these forecasts, the new intensity forecast shows steady intensification through 48 h, followed by a slower rate of development during the remainder of the forecast period. The new forecast is an update of the previous forecast. It should be noted that there is some guidance that suggests a possibility Erin could intensify further than shown in the official forecast. The initial motion is now 280/15 kt. The storm continues to be steered by a subtropical ridge to the north, and this ridge should steer the cyclone generally west-northwestward during the next three days. After that time, the western portion of the ridge is forecast to weaken or break due to the influence of the mid-latitude westerlies over the northeastern United States. This evolution should lead to Erin turning toward the northwest or north-northwest during the remainder of the forecast period, although there remains significant spread in the guidance on just how sharp this turn will be. The new forecast track is a little south of the previous track through 72 h, and then it is nudged a little to the west of the previous track at 96 and 120 h. Due to the spread in the track guidance later in the forecast period, 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. Heavy rainfall across the northernmost Leeward Islands, the U.S. and British Virgin Islands, as well as southern and eastern Puerto Rico, may lead to isolated flash and urban flooding, along with landslides or mudslides this weekend into early next week. 2. Tropical storm conditions are possible for portions of the northern Leeward Islands, where Tropical Storm Watches are in effect, beginning on Saturday as the core of Erin passes north of those islands. Tropical storm conditions could also occur in portions of the Virgin Islands and Puerto Rico later in the weekend, and additional watches may be required tonight or on Friday. 3. 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. FORECAST POSITIONS AND MAX WINDS INIT 14/2100Z 16.7N 51.2W 50 KT 60 MPH 12H 15/0600Z 17.3N 53.5W 55 KT 65 MPH 24H 15/1800Z 18.1N 56.6W 65 KT 75 MPH 36H 16/0600Z 19.0N 59.5W 80 KT 90 MPH 48H 16/1800Z 19.8N 62.2W 90 KT 105 MPH 60H 17/0600Z 20.8N 64.4W 95 KT 110 MPH 72H 17/1800Z 21.7N 66.1W 100 KT 115 MPH 96H 18/1800Z 24.2N 68.9W 105 KT 120 MPH 120H 19/1800Z 27.2N 70.3W 110 KT 125 MPH $$ Forecaster Beven