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| #1249524 (Received by flhurricane at: 4:57 AM 25.Oct.2025) TCDAT3 Tropical Storm Melissa Discussion Number 16 NWS National Hurricane Center Miami FL AL132025 500 AM EDT Sat Oct 25 2025 During the last center fix of the Air Force Reserve mission into Melissa several hours ago, a dropsonde measured a surface pressure of 989 mb with winds of 27 kt, suggesting that the central pressure has fallen to about 986 mb. The plane did not measure stronger winds, but it did not fly through the area due east of the center, which is where a nearly coincident ASCAT pass suggested the strongest winds would be located. Some westerly shear is still evident, but the center is now embedded far enough under the Central Dense Overcast to yield Dvorak estimates of T4.0/65 kt from TAFB and T3.5/55 kt from SAB. The current intensity is estimated to be 60 kt based on all these data. It`s also worth noting that an eye feature has occasionally been apparent in radar images from Jamaica. Melissa is currently moving slowly northwestward (310/3 kt). Steering currents will remain weak for the next 3 days, and Melissa is forecast to drift westward through Sunday night to the south of Jamaica. A sharp but still very slow turn toward the north is expected Monday and Monday night. Unfortunately, a large majority of the latest reliable track models show Melissa making landfall on Jamaica in about 72 hours. What`s most concerning here is that the island is likely to experience a couple of days of heavy rainfall and tropical-storm-force winds before the core--and strongest winds--even reach the coast. An increase in forward motion is expected by days 4 and 5, with Melissa accelerating northeastward across eastern Cuba, the southeastern Bahamas, and the Turks and Caicos Islands. Although there are some speed differences among the models, for the most part the cross-track spread is generally small. Although some westerly shear is likely to continue for the next few days, high oceanic heat content and stronger upper-level divergence should be able to support significant strengthening. The dynamical model-based Rapid Intensification (RI) indices (DTOPS) in particular are quite aggressive, showing a very high probability of a 55-kt increase in intensity over the next 48 hours. In addition, 41 of the 50 Google DeepMind ensemble members show Melissa at category 4 or 5 strength by Monday afternoon (60 hours), which is the same time that the NHC forecast continues to show a peak intensity of 135 kt. Although some slight weakening is possible after 60 hours, possibly due to the circulation interacting with land and/or an eyewall replacement, Melissa still has a significant possibility of making landfall on Jamaica as a major hurricane. Melissa could maintain major hurricane strength when it reaches eastern Cuba, but increased shear should lead to weakening below major hurricane strength by day 5. Key Messages: 1. Jamaica: Melissas slow movement will bring a multi-day period of damaging winds and heavy rainfall beginning tonight, likely causing catastrophic flash flooding and numerous landslides. There is an increasing risk of life-threatening storm surge early next week. All preparations should be completed today. 2. Haiti: Catastrophic flash flooding and landslides are expected across southwestern Haiti into early next week, likely causing extensive infrastructural damage and potentially prolonged isolation of communities. Immediate preparations to protect life and property are urged. Strong winds could also potentially last for a day or more over the Tiburon peninsula. 3. Dominican Republic: Heavy rainfall could produce potentially catastrophic flash flooding and numerous landslides in southern regions. 4. Eastern Cuba, Bahamas, and the Turks and Caicos: Monitor Melissa closely. There is an increasing risk of a significant storm surge, damaging winds, and heavy rainfall by the middle of next week. In eastern Cuba, the risk of life-threatening flash flooding and landslides is increasing. FORECAST POSITIONS AND MAX WINDS INIT 25/0900Z 16.3N 75.0W 60 KT 70 MPH 12H 25/1800Z 16.5N 75.3W 75 KT 85 MPH 24H 26/0600Z 16.7N 75.9W 100 KT 115 MPH 36H 26/1800Z 16.8N 76.5W 115 KT 130 MPH 48H 27/0600Z 16.9N 77.1W 125 KT 145 MPH 60H 27/1800Z 17.2N 77.4W 135 KT 155 MPH 72H 28/0600Z 17.8N 77.2W 125 KT 145 MPH...S COAST OF JAMAICA 96H 29/0600Z 20.4N 75.3W 105 KT 120 MPH...SOUTHEASTERN CUBA 120H 30/0600Z 24.8N 71.6W 90 KT 105 MPH...OVER WATER $$ Forecaster Berg |
