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| #1249154 (Received by flhurricane at: 10:36 PM 21.Oct.2025) TCDAT3 Tropical Storm Melissa Discussion Number 3 NWS National Hurricane Center Miami FL AL132025 1100 PM EDT Tue Oct 21 2025 Melissa continues to be under the influence of significant westerly vertical wind shear. The center of the storm appears to be exposed to the west of a cluster of very deep convection, and overall the system is not very well organized with poorly-defined banding features. The advisory intensity is held at 45 kt in agreement with a Dvorak classification from TAFB, though objective intensity estimates from UW-CIMSS are somewhat lower. An Air Force Reserve Unit Hurricane Hunter aircraft is scheduled to investigate the tropical cyclone in a few hours and should provide a good intensity estimate. Melissa remains an asymmetric storm with most of the strong winds over the northeastern and eastern portions of the circulation. The system continues to move a little southwest of the previous track with an initial motion estimate of 270/11 kt. The track forecast for the next several days remains quite challenging. Melissa is likely to remain in a region of weak steering currents for most of this week. Once again, the GFS model looks like an outlier with a track across Hispaniola by this weekend and most of the other guidance much farther south and west. The future track depends, among other things, on how strong and vertically deep Melissa will become while it is over the Caribbean, and how much a mid-level trough digs along the U.S. east coast during the next 5 days. A stronger tropical cyclone would likely move more northward or northeastward than a weak system would. The new official forecast is shifted somewhat west of the previous one and is in good agreement with the dynamical model consensus and the FSU Superensemble solution. The latest Google DeepMind ensemble mean is just a little to the left of the official forecast. Water vapor imagery continues to show upper-level westerlies ahead of Melissa, and the shear is not likely to decrease much over the next few days. The SHIPS guidance using the large-scale predictors from the ECMWF model indicates some relaxation of the shear in 3-5 days. The official intensity forecast, like the previous one, shows strengthening into a hurricane by the latter part of the forecast period. This is in good agreement with the LGEM guidance. However it should be noted that this is a low-confidence intensity forecast. 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 22/0300Z 14.2N 74.0W 45 KT 50 MPH 12H 22/1200Z 14.6N 74.6W 45 KT 50 MPH 24H 23/0000Z 15.1N 75.2W 50 KT 60 MPH 36H 23/1200Z 15.6N 75.6W 55 KT 65 MPH 48H 24/0000Z 15.9N 75.8W 55 KT 65 MPH 60H 24/1200Z 16.3N 75.8W 60 KT 70 MPH 72H 25/0000Z 16.9N 75.7W 60 KT 70 MPH 96H 26/0000Z 17.5N 76.1W 65 KT 75 MPH 120H 27/0000Z 17.6N 76.2W 75 KT 85 MPH $$ Forecaster Pasch |
