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| #1249127 (Received by flhurricane at: 4:48 PM 21.Oct.2025) TCDAT3 Tropical Storm Melissa Discussion Number 2 NWS National Hurricane Center Miami FL AL132025 500 PM EDT Tue Oct 21 2025 Satellite data indicate that Melissa is struggling in strong shear, which has been the theme for many systems over the deep tropics this year. The low-level center of the storm is exposed to the west of the main area of thunderstorms. Air Force Hurricane Hunters have been investigating the system this afternoon and found that the minimum pressure is around 1003 mb. Based on their observations, ASCAT passes, and Dvorak estimates, the initial intensity is held at 45 kt. Melissa`s wind field is also quite asymmetric, with most of the tropical-storm-force winds occurring on the system`s east side. Some of the outermost northern bands are approaching Hispaniola, and these heavy rains are expected to spread across that island during the next couple of days. Melissa is a little south of the previous track and it continues to move westward at about 13 kt. There has been no change to the track forecast scenario, which remains complicated. Over the next couple of days, there is fair confidence that Melissa should slow down and gradually turn to the northwest or north and approach Haiti and Jamaica late this week. The motion after that appears to be linked to how strong and vertically aligned the system gets, and that is when the models diverge. If Melissa organizes like the GFS predicts, it could turn northeastward into the weakness in the ridge and move over Hispaniola. Conversely, if Melissa remains sheared and lopsided, it will likely stall and eventually drift westward as a ridge builds north of it. Given the expected continued shear, the NHC track forecast leans toward the latter scenario. This prediction is a little left of the previous forecast and remains a blend of the latest Google DeepMind ensemble mean, the corrected consensus aid HCCA, and simple consensus TVCA. Although the ocean is very warm, the models suggest that the vertical wind shear could persist over Melissa during the next few days. In addition, there is also some dry air in the storm`s vicinity. Based on these mixed signals, the strengthening trend is expected to be slow. In fact, the new guidance supports nudging the short term intensity down a bit. If Melissa remains over the Caribbean late this week and over the weekend, the upper-level winds could become more conducive for more significant strengthening. The NHC intensity forecast is in best agreement with the HCCA model. Key Messages: 1. Melissa is expected to bring heavy rainfall and the risk of significant flash flooding and the danger of landslides to portions of Haiti and the Dominican Republic through the weekend. 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 21/2100Z 14.2N 73.0W 45 KT 50 MPH 12H 22/0600Z 14.5N 73.7W 45 KT 50 MPH 24H 22/1800Z 15.0N 74.4W 50 KT 60 MPH 36H 23/0600Z 15.5N 75.0W 55 KT 65 MPH 48H 23/1800Z 16.1N 75.1W 60 KT 70 MPH 60H 24/0600Z 16.5N 75.0W 60 KT 70 MPH 72H 24/1800Z 16.9N 75.0W 60 KT 70 MPH 96H 25/1800Z 17.3N 75.0W 65 KT 75 MPH 120H 26/1800Z 17.5N 75.2W 75 KT 85 MPH $$ Forecaster Cangialosi |
