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| #1249289 (Received by flhurricane at: 4:51 AM 23.Oct.2025) TCDAT3 Tropical Storm Melissa Discussion Number 8 NWS National Hurricane Center Miami FL AL132025 500 AM EDT Thu Oct 23 2025 Melissa continues to struggle in strong westerly vertical wind shear. Surface observations and Air Force aircraft data show that the system is vertically tilted with the low-level center partially exposed and located nearly 100 miles west of the mid-level center that is apparent in satellite images. The wind field of the storm also remains lopsided, with most of the strong winds confined to the eastern half of the circulation. The initial intensity is held at 45 kt, but this is probably generous based on the aircraft data and an ASCAT pass from last evening. The storm has been crawling and moving erratically. In general, Melissa is likely to inch northward during the next 36 to 48 hours as the storm is influenced by a weakness in the subtropical ridge. By late Friday, a mid-level ridge is forecast to build eastward to the north of the storm, and that pattern change should induce a slow westward or west-northwestward motion over the weekend. By early next week, that ridge is expected to move away as a large-scale trough amplifies over the eastern U.S. This change in the steering flow should cause Melissa to begin to gain more latitude again by the end of the forecast period. Given the complex steering pattern and continued model differences in the predicted vertical depth of Melissa, there remains a significant spread in the deterministic guidance and the ensemble solutions. One thing we feel confident about is that Melissa is likely to move slowly and remain in the vicinity of Haiti, Jamaica, and eastern Cuba for several days. The NHC track forecast is shifted a little to the right of the previous one, trending toward a blend of the latest Google DeepMind ensemble mean and HCCA solution. The current westerly vertical wind shear over Melissa is expected to linger for about another day, and that should keep the storm at around the same intensity during that time. However, after that, the upper-level wind pattern will gradually become more conducive while the system remains over the very warm waters of the central and northwestern Caribbean Sea. These conditions should allow Melissa to become vertically aligned and strengthen significantly. In fact, rapid intensification appears likely this weekend and early next week. The NHC intensity forecast lies near the middle of the guidance envelope from 12 to 72 hours, but leans toward the upper end of the guidance at days 4 and 5. As Melissa intensifies, its wind field is expected to grow and become more symmetric. Key Messages: 1. Melissa is expected to meander over the central Caribbean Sea for several days and is forecast to become a major hurricane by late this weekend or early next week. Interests in Jamaica, Haiti, Cuba, and the Dominican Republic are urged to continue monitoring the latest forecasts. 2. Due to Melissas slow motion, the risk of a prolonged period of strong winds, possibly lasting for a day or more, is increasing for Jamaica and the Tiburon peninsula of Haiti. Preparations to protect life and property should be rushed to completion, since strong winds could begin in these areas on Friday and continue increasing over the weekend. 3. Melissa is expected to produce heavy rainfall across portions of the Dominican Republic, Haiti, and Jamaica through the weekend, bringing a risk of significant, life-threatening flash flooding and numerous landslides. FORECAST POSITIONS AND MAX WINDS INIT 23/0900Z 15.0N 74.9W 45 KT 50 MPH 12H 23/1800Z 15.2N 75.0W 45 KT 50 MPH 24H 24/0600Z 15.6N 75.0W 50 KT 60 MPH 36H 24/1800Z 16.0N 75.0W 55 KT 65 MPH 48H 25/0600Z 16.4N 75.1W 60 KT 70 MPH 60H 25/1800Z 16.6N 75.4W 70 KT 80 MPH 72H 26/0600Z 16.7N 76.0W 85 KT 100 MPH 96H 27/0600Z 16.9N 77.0W 105 KT 120 MPH 120H 28/0600Z 17.1N 78.0W 115 KT 130 MPH $$ Forecaster Cangialosi |
