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| #1249184 (Received by flhurricane at: 5:09 AM 22.Oct.2025) TCDAT3 Tropical Storm Melissa Discussion Number 4 NWS National Hurricane Center Miami FL AL132025 500 AM EDT Wed Oct 22 2025 Data from an Air Force Reserve Hurricane Hunter aircraft has been extremely useful in showing that the center of Melissa has re-formed to the northeast of the previous center. Earlier scatterometer data had already shown an elongated circulation, and the very deep convection combined with the moderate westerly shear has caused the re-formation. The initial intensity is kept at 45 kt, a compromise between somewhat lower aircraft winds but also lower central pressure, now at 1000 mb. The initial motion is estimated, with low confidence, to be 295/6. Melissa is forecast to move very slowly to the northwest and north-northwest during the next few days into a weakness by an approaching mid-latitude trough. There continues to be a very large uncertainty on whether the storm would turn more into the weakness and threaten Haiti or Cuba, or whether it would turn more westward to the south of Jamaica as a ridge rebuilds over the Bahamas, with reliable models in either camp. This appears to be somewhat tied to the storm`s structure, with the less vertically coherent model solutions generally ending up on the western side of the track envelope this weekend, and stronger initial storm representations on the northeastern side. With such a distinct track bifurcation noted in the guidance (excluding the consensus aids) and dependence on structure, this should be considered an extremely uncertain forecast, and significant changes could be required. The model trends have been favoring the more westward solutions recently, and the official forecast is nudged in that direction at long range. Melissa is likely to be encountering moderate wind shear for the next few days, counteracted by the very warm and moist conditions in the Caribbean Sea. This pattern favors slow intensification through that time. At long range, some relaxation of this shear is anticipated with the more equatorward storm solutions showing the most conducive environment. The new NHC wind speed prediction is much higher than the last one by day 5, but still lower than the model consensus due to continuity constraints. While there is still a large forecast intensity uncertainty, the chances of a major hurricane increase if this forecast were to trend farther southwest at long range, similar to many of the recent regional hurricane model forecasts. Key Messages: 1. Melissa is expected to produce heavy rainfall across portions of the Dominican Republic, Haiti, and Jamaica through this weekend, bringing a risk of significant flash flooding and landslides. 2. Hurricane conditions are possible in the southwestern peninsula of Haiti where a Hurricane Watch is in effect. A Tropical Storm Watch is in effect for Jamaica. Preparations to protect life and property should be completed by Thursday. 3. There is significant uncertainty in the track and intensity forecast of Melissa. Interests elsewhere in Hispaniola and Cuba should continue to monitor the latest forecasts. FORECAST POSITIONS AND MAX WINDS INIT 22/0900Z 14.3N 73.5W 45 KT 50 MPH 12H 22/1800Z 14.7N 74.3W 45 KT 50 MPH 24H 23/0600Z 15.2N 74.9W 50 KT 60 MPH 36H 23/1800Z 15.6N 75.1W 55 KT 65 MPH 48H 24/0600Z 16.0N 75.2W 60 KT 70 MPH 60H 24/1800Z 16.3N 75.3W 65 KT 75 MPH 72H 25/0600Z 16.7N 75.5W 70 KT 80 MPH 96H 26/0600Z 17.0N 76.0W 80 KT 90 MPH 120H 27/0600Z 17.0N 76.5W 90 KT 105 MPH $$ Forecaster Blake |
