Issued at 500 PM EDT Wed Oct 22 2025
000 WTNT43 KNHC 222042 TCDAT3 Tropical Storm Melissa Discussion Number 6 NWS National Hurricane Center Miami FL AL132025 500 PM EDT Wed Oct 22 2025 Like yesterday, Melissa's structure has come unglued this afternoon, with the low-level circulation becoming exposed to the west of the bursting deep convection. While that convection continues to have very cold cloud tops, it lacks much organization, remaining parked down-shear of the storm with 20-30 kt of west-northwesterly shear undercutting the outflow layer. This disjointed structure is nicely exhibited on an 1825 UTC AMSR2 pass. While the objective intensity estimates in general are a little higher than this morning, the subjective Dvorak estimates are lower, and given the disjointed structure of Melissa, it favors holding the intensity at 45 kt this advisory. Another Air Force Reserve and the first NOAA Hurricane Hunter mission will be in the storm this evening to provide more structural information. Melissa has taken a short-term jog westward as it became exposed, but now appears to be resuming a very slow west-northwestward motion at 290/2 kt. The track reasoning remains similar to the previous forecast over the next 2-3 days, with the forecast storm structure likely to have a significant role in the future track. Dynamical models that show the storm becoming more vertically aligned and deep (GFS, HWRF) show Melissa turning north or northeastward due to westerly deep-layer steering into a weakness induced by a broad upper-level trough located over the Bahamas. However, models that show Melissa remaining more shallow and misaligned (ECMWF, HAFS-A/B) maintain a northwestward or north-northwestward component of motion. Compared to this morning, the track guidance has shifted slower and farther west, possibly due to the farther west initial position. The NHC track has been shifted westward and is also a little southward after 60 h, but remains farther north and east of the ECMWF and HAFS models this cycle, and is roughly in between the HFIP consensus approach (HCCA) and Google DeepMind ensemble mean (GDMI). This track forecast favors the models that keep Melissa weak and less prone to the deep-layer steering over the next 24-48 hours. However, this remains a low confidence track forecast other than Melissa maintaining a slow motion for the majority of the period. The current vortex misalignment of Melissa is a significant impediment to short-term intensification, and the vertical wind shear is expected to maintain this tilted structure over the next 24-36 hours, although I can't preclude any center reformations down-shear, like what occurred last night. After this period, the ECWMF-SHIPS guidance now indicates the ongoing westerly shear will decrease to 10-15 knots, and the storm remains over very warm sea-surface temperatures and high oceanic heat content. The hurricane-regional models have all responded by showing significant intensification after the vortex becomes vertically aligned, sometime in the 60-96 h period, though timing when this may occur is challenging. The intensity guidance is once again higher than the previous cycle, and the NHC intensity forecast was raised once again, showing Melissa becoming a hurricane in 72 h, rapidly intensifying into a major hurricane by 96 h, with additional intensification likely thereafter. This forecast is in the best agreement with the HCCA intensity aid, but it is worth noting it's under the latest HAFS-A/B and HMON forecasts. Unfortunately, it is becoming increasingly likely that Melissa will become a large and dangerous hurricane by the end of the forecast period. Key Messages: 1. Melissa is forecast to meander over the central Caribbean Sea and could potentially become a major hurricane by early next week. Interests in Jamaica, Haiti, Cuba, and the Dominican Republic are urged to continue monitoring the latest forecasts. 2. Due to Melissa’s 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 as early as late Thursday or 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 this weekend, bringing a risk of significant, life-threatening flash flooding and numerous landslides. FORECAST POSITIONS AND MAX WINDS INIT 22/2100Z 14.4N 74.3W 45 KT 50 MPH 12H 23/0600Z 14.6N 74.5W 45 KT 50 MPH 24H 23/1800Z 14.9N 74.6W 50 KT 60 MPH 36H 24/0600Z 15.2N 74.7W 50 KT 60 MPH 48H 24/1800Z 15.6N 74.8W 55 KT 65 MPH 60H 25/0600Z 16.1N 75.0W 60 KT 70 MPH 72H 25/1800Z 16.3N 75.6W 70 KT 80 MPH 96H 26/1800Z 16.2N 76.7W 100 KT 115 MPH 120H 27/1800Z 16.0N 78.0W 115 KT 130 MPH $$ Forecaster Papin
