Issued at 500 AM AST Wed Aug 13 2025
000 WTNT45 KNHC 130843 TCDAT5 Tropical Storm Erin Discussion Number 8 NWS National Hurricane Center Miami FL AL052025 500 AM AST Wed Aug 13 2025 Deep convection is redeveloping intermittently over the western portion of Erin's circulation. However the system continues to have a rather ragged-looking appearance, with limited convective banding features. There appears to be some easterly shear over the storm at this time. Subjective Dvorak classifications are a little below tropical storm strength and objective intensity estimates from UW-CIMSS are generally in the 35-40 kt range. Based on these estimates, the advisory intensity remains at 40 kt. Erin has not been able to strengthen significantly for the past couple of days, likely due to marginal SSTs, and a relatively dry mid- to lower-tropospheric air mass. However, it is expected that the system's environment will gradually become more conducive for intensification over the next 48 hours. In particular, Erin will be traversing progressively warmer ocean waters with likely a little less environmental subsidence. The official intensity forecast is similar to the previous ones and continues to call for Erin to become a hurricane later this week. This is also supported by the corrected model consensus, HCCA, and Google DeepMind model guidance. Although the center is not easy to locate, it is estimated that the cyclone is continuing on its generally westward track, at about 260/17 kt. A strong low- to mid-level ridge is situated to the north of Erin, and in a few days a slight weakness develops in the ridge near 65W longitude. This should cause the tropical cyclone to begin to move west-northwestward at a slightly slower forward speed in a couple of days. The track guidance is in fairly good agreement, and the official forecast is close to the HCCA solution and is on the southern side of the model track forecast suite. This is also very similar to the previous NHC prediction. Users are reminded that NHC track forecasts have an average error of 120-180 n mi (150-215 statute miles) at days 4 and 5, and future adjustments to the forecast are still possible. KEY MESSAGES: 1. Erin could move close enough to the northern Leeward Islands, the Virgin Islands, and Puerto Rico over the weekend to produce some impacts on those islands. However, the magnitude of those impacts is still not known, and interests there should continue to monitor the progress of this storm. 2. There is even greater uncertainty in what impacts might occur in portions of the Greater Antilles, the Bahamas, the east coast of the United States, and Bermuda next week. 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 13/0900Z 16.5N 41.9W 40 KT 45 MPH 12H 13/1800Z 16.4N 44.1W 45 KT 50 MPH 24H 14/0600Z 16.5N 47.1W 50 KT 60 MPH 36H 14/1800Z 17.0N 50.0W 55 KT 65 MPH 48H 15/0600Z 17.8N 52.9W 65 KT 75 MPH 60H 15/1800Z 18.6N 55.8W 75 KT 85 MPH 72H 16/0600Z 19.5N 58.7W 85 KT 100 MPH 96H 17/0600Z 21.3N 63.5W 100 KT 115 MPH 120H 18/0600Z 23.4N 66.8W 100 KT 115 MPH $$ Forecaster Pasch