Matt Lanza

Melissa continues to look like a slow-moving disaster for parts of the Caribbean

In brief: Melissa will struggle for another day or so before it likely explodes into a major hurricane near Jamaica, yielding a lot of bad things. We are most troubled by the flooding potential in Haiti, eastern Cuba, and Jamaica. Whatever the case, this is going to be a destructive, very bad storm for those locations.

(NOAA/NHC)

How Melissa should go from mess to might

Tropical Storm Melissa continues to oscillate in intensity today, now down to 45 mph maximum sustained winds. We figured it would be a slog at first, and it is just that.

Tropical Storm Melissa looking rather discombobulated on satellite this evening. (Weathernerds.org)

It is battling wind shear mightily at the moment, which is basically causing the storm to be tilted. The actual surface center is to the west of the thunderstorms, while the upper level center of the storm is located to the east of there. You can see on the animation below how the center of the system tilts with height from the surface to 20,000 feet up (500 mb level).

The center of Melissa is skewed with height to the east, indicative of strong wind shear. (Tropical Tidbits)

Strong wind shear will do that! Now, over the next 48 hours, that shear is going to diminish. This will allow the system to better vertically align. In fact, by Sunday, per the European model below, you can see how the surface, 5,000′ (850 mb), 10,000′ (700 mb), and 20,000′ (500 mb) centers are basically all atop each other rather than skewed to the east.

As wind shear relaxes, Melissa will become vertically “stacked” and rapid intensification should ensue. (Tropical Tidbits)

As Melissa vertically aligns, it will become stronger. And then the process will basically start a feedback loop, allowing Melissa to feast on a more pristine environment of low wind shear and incredibly warm water. The combination should allow for explicit rapid intensification of Melissa very near Jamaica. As this occurs, Melissa will become a powerful, extremely dangerous storm by Sunday or Monday.

How strong does Melissa get?

Much like the last few days, the sky is the limit with Melissa, as long as wind shear relaxes and it remains over water. With steering currents basically allowing Melissa to meander the next 18 to 36 hours, possibly northward, when they allow for a slow west drift late this weekend, it will depend on whether or not Melissa hugs the coast of Jamaica or remains offshore that will determine how strong it ultimately gets. Hurricane? Almost a guarantee. Major hurricane? Probably. Cat 4 or 5? Seems like a better than average risk. Consensus modeling puts it as a higher end category 3 storm, while Google Deep Mind and the HAFS model suite take it well into category 4 intensity. That’s where the NHC forecast sits right now, which makes a lot of sense given the environment.

Intensity forecasts run the gamut, but some of the best performing models this season indicate higher end category 3 or category 4 intensity by Sunday and Monday. (Tropical Tidbits)

It appears that Melissa’s intensity will peak in the 72 to 120 hour period, while the storm is in the Caribbean near, south, or just southwest of Jamaica. This also places it near or over the highest oceanic heat content in the basin, meaning it will be ideally situated for high-end intensification. The sky remains the limit, barring land interaction.

Catching Melissa’s Drift

As Melissa drifts westward thanks to basically collapsed steering currents and high pressure to the north gently nudging it to the west, it will remain in rather close proximity to Jamaica, likely lashing the island with hurricane conditions for perhaps 2 full days or more. This reminds me a little of how Dorian stopped moving near Great Abaco and Grand Bahama Island in 2019 as a category 5 storm. The terrain in Jamaica means that the proximity to land will dictate things a little more, but the general idea is that you’re going to have a massive storm at or near peak intensity in very close proximity to land, in this case Jamaica.

Eventually, as a trough digs into the Eastern U.S., it will begin to try to capture Melissa allowing it to turn northward and track toward Cuba. However, while this process begins after Tuesday, it probably won’t accelerate out to sea until Thursday. So it may take another day and a half to get from west of Jamaica to Cuba itself.

Ensemble means take Melissa close to the southeast coast of Cuba by early Wednesday. Trends have been to slow this down a bit since earlier this week. (Polarwx.com)

From there, Melissa will slowly exit, probably over the southeastern Bahamas and out to sea, hopefully closing the books on the 2025 hurricane season.

The flooding

Melissa is going to be a terrible storm. There are just no two ways about this. It’s going to be hour after hour of lashing. Even if that’s not at major hurricane intensity on land in Jamaica, it will be powerful. And it will rain. A ton. I’ve shown the forecast for rain, but unfortunately because Melissa is staying at the Residence Inn and not the Holiday Inn Express, 72 hours doesn’t cover the entire forecast. Here’s a look at the forecast from today’s European model. Keep in mind that these totals will vary a bit, and the exact totals will depend on the exact track, but for Jamaica, this is absolutely horrid.

European model rainfall totals range from 15 to 35 inches across Jamaica through next week. (Weathernerds.org)

Unfortunately, it’s tough to argue that these totals can’t be achieved. The slow movement and rapid intensification should allow for this to occur. Additionally, heavy rain is likely in eastern Cuba and southwest Haiti.

European model forecast for rain through next week across the Caribbean and Bahamas. (Weathernerds.org)

Perhaps 20 inches of rain could fall in those areas too. This seems increasingly likely to be a catastrophic rain and flooding event in addition to a very bad hurricane for Haiti, eastern Cuba, and Jamaica. Sometimes you just feel helpless when you look at things like this, knowing the message is clear, the uncertainty not terribly high, but the end result will still be terrible. Here’s hoping somehow it underperforms.

More tomorrow.

Melissa to torment portions of the Caribbean, especially parts of Jamaica, with days of heavy rain and potentially catastrophic flooding concerns

In brief: Just a quick update on Melissa this morning. A more comprehensive update will be posted this evening.

Melissa remains disorganized this morning, with max winds of 50 mph.

Melissa continues to struggle a bit, though continues to have deep thunderstorm activity. (Weathernerds.org)

There have been minimal track or intensity forecast changes since yesterday.

Melissa’s track brings it a little closer to Jamaica than yesterday’s forecasts. (NOAA/NHC)

The biggest change is perhaps tracking it a little closer to Jamaica by next week. Tropical Storm Warnings are now posted for Jamaica, with Hurricane Watches for both Jamaica and southwest Haiti. A major hurricane is expected by late this weekend.

The rainfall forecast for Melissa remains ominous, with 12 inches (300mm) or more possible through the weekend in Jamaica.

Melissa’s rainfall forecast through Sunday morning. Additional high-end rains will follow this. (NOAA WPC)

When you factor in that this rainfall forecast is through Sunday morning, and there will be at least a couple more days of torrential rain to follow, portions of Jamaica could be in line for 20 to 30 inches (500-750mm) of rainfall before all is said and done. It’s an extremely concerning situation, particularly given that tropical storm, if not hurricane conditions may accompany those rains much of the time. We urge the strongest precautions for folks in Jamaica with respect to flooding in particular, but also for tropical storm and hurricane conditions.

We’ll be back later today with more color on this.

Melissa’s steadiness foretells a rather lengthy stay in the Caribbean, increasing the odds of explosive intensification later this weekend

In brief: Melissa’s intensity has held today, increasing the odds that it will remain in the Caribbean through the weekend, eventually finding a more hospitable environment for rapid, possibly explosive intensification this weekend. Significant impacts are likely for parts of the central Caribbean, particularly Jamaica, and Melissa may stick around well into next week. Eventually the storm will be picked up and carried northward into the Atlantic, but probably not before becoming a powerful, destructive storm in parts of the central or western Caribbean.

Tropical Storm Melissa is continuing to absolutely crawl west at a whopping 1 mph this evening. Melissa has not gained any strength today, and that’s not shocking. One of the problems with Melissa is that its general lower-end intensity early on is causing it to miss one exit ramp that it could otherwise take that would perhaps spare some of the central Caribbean a truly bad storm.

Melissa is expected to very slowly organize in the coming days before perhaps explosively intensifying after Saturday. (Polarwx.com)

In the meantime, with some 20 to 30 kts of shear buffeting the storm, it’s going to remain loosely organized. Reconnaissance aircraft are investigating the storm this evening, so we’ll see what they find.

Forecast-wise, not much has changed since this morning. The requisite tropical storm and hurricane watches remain posted. Melissa’s future track depends heavily on its structure. If the storm remains fairly disorganized, as expected by AI modeling and the European model, we will continue to see this drift northwest or west-northwest. If it can suddenly pull itself together, it will quickly feel the westerlies to the north that will pick it up and grab it and lift it out of the Caribbean and into the open Atlantic. The GFS model tends to favor this. Given the current disorganization, odds seem to favor the weaker, more time over warm water scenarios, eventually putting Melissa in extraordinarily warm waters with lower wind shear.

(Via Google Weather Lab)

Once it gets there, the sky is the limit. As we noted earlier today, extreme levels of oceanic heat content will be around to fuel Melissa for a longer time than a typical slow-moving storm. This likely means that we’re looking at a high-end major hurricane eventually by late this weekend or early next week. Its proximity to land will determine just how bad the impacts get, specifically for places like Jamaica, eastern Cuba, Haiti, or even Central America. But suffice to say, it looks ominous right now.

It will take a very strong upper level trough exiting the U.S. to pick up Melissa and pull it out of the Caribbean next week.

Melissa exits the Caribbean next week, probably after Tuesday. (Tropical Tidbits)

Theoretically, this should be a straightforward exercise: Trough digs into the East, captures Melissa on its way off the coast, and the storm exits. There’s still a fair bit of uncertainty on that last point, and we’ll want to watch how that trough progresses in the days ahead. Folks in eastern Cuba, the Bahamas, Turks and Caicos, and even Bermuda should be following Melissa’s progress closely next week. Folks on the East Coast don’t need to worry right now, but as noted, we should continue watching things.

More tomorrow morning.

Melissa’s slow path in the Caribbean likely to cause the most impactful storm of the 2025 season

In brief: Tropical Storm Melissa is unfortunately looking to be one of the most impactful storms of the Atlantic hurricane season, with several days of high-end impacts possible for places like Jamaica and Haiti. Risks of a high-end major hurricane, along with catastrophic rainfall exist in these areas through the weekend and into early next week. Melissa is not a threat to the U.S. at this time, though it may graze the Bahamas or Turks and Caicos on its way out next week.

Invest 98L was upgraded to Tropical Storm Melissa on Tuesday, in what looks like the beginning of the climax of the 2025 Atlantic hurricane season. The forecast track for Melissa is troublesome.

(NOAA/NHC)

Melissa is expected to crawl, I mean crawl in the central Caribbean over the next several days. Melissa is not terribly well organized this morning, though its satellite appearance is rather ominous. In fact, the center is fairly heavily displaced to the west within the deeper thunderstorm activity indicated by the brighter white and pink/purple colors on the satellite image below.

Melissa’s satellite presentation isn’t particularly aesthetic despite being ominous. (Tropical Tidbits)

Maximum sustained winds are 50 mph as of the 8 AM advisory. We’ll see if that nudges up for the 11 AM ET one. There is currently a Hurricane Watch for southwest Haiti from Port-Au-Prince to the border with the Dominican Republic. A Tropical Storm Watch is posted for Jamaica. These watches could be upgraded to warnings and/or adjusted further later today.

Melissa’s slow track forward

So where is Melissa going to go? The billion dollar question, of course. Yesterday, it seemed we had a consensus of slow-moving and eventually a sharp turn north or northeast, perhaps toward Hispaniola. That’s still on the table, but the key now may be the “slow-moving” aspect of it all. Over the next 2 days we’ll see very slow west-northwest movement and drift. By Friday morning, we expect to see Melissa sitting just southeast of Jamaica.

Euro ensemble, and various Google AI model members forecast on Friday morning. (Google Weather Lab)

A continued northwest-ward drift is expected to continue beyond Friday, but from there, it gets a lot more complicated. Steering currents are meager at best in the Caribbean, meaning that we may see Melissa drift west even beyond this weekend into next week. It may take until later next week for a strong trough in the upper atmosphere to actually capture Melissa and steer it north and out to sea.

Of course, if Melissa just continues slowly drifting west, that may mean days of impacts for places like Haiti and Jamaica and possibly even eastern Cuba, the Cayman Islands or portions of Nicaragua and Honduras.

How strong will Melissa get?

Oceanic heat content is always high in the Caribbean, but this year it’s very, very high.

Oceanic heat content anomaly in the Caribbean is the third highest we’ve seen this late in the season. (Brian McNoldy, University of Miami)

In fact, based on Argo buoy temperature reports from the Caribbean, 30°C water extends down about 180 feet below the surface of the Caribbean. It’s deep, rich, warm water. Particularly if for some reason this ends up west of Jamaica, the oceanic heat content there is incredibly high.

Truthfully, the only things that may inhibit intensification of Melissa is land and time. Wind shear is always a concern, but frankly, there’s nothing that stands out dramatically right now, certainly nothing that says this will falter. If Melissa drifts west to south of Jamaica where that patch of extreme oceanic heat content lies, we could easily be talking a category 4 or 5 storm.

Extreme levels of oceanic heat content exist south of Jamaica, possibly on the path of Melissa. (Brian McNoldy, University of Miami)

So steady intensification is likely for Melissa over the next couple days. Odds of rapid intensification upwards of 75 mph in the next 3 days are almost 5 times normal. Bottom line: There is likely to be continued intensification of Melissa and based on the track, the ceiling could be extremely high.

Rain forecast

Regardless of the track and intensity, someone, perhaps a lot of folks will see heavy, heavy rainfall in the Caribbean.

The rainfall forecast through Sunday shows upwards of a foot of rainfall for eastern Jamaica, as well as the south coasts of Haiti and the Dominican Republic. (NOAA WPC)

When all is said and done next week, it is not out of the realm of the possible for some places to see 20 inches (500 mm) or more of rainfall. This could be catastrophic in some places, including portions of Jamaica and Haiti or the southern Dominican Republic as well. Just really bad news with a slow-moving Melissa.

In summary:

  • Melissa is going to move slowly over the next 5 to 7 days over some of the warmest, deepest warm water in the Atlantic Basin.
  • Intensification into a hurricane and major hurricane seems likely at this point, with a high-end category 4 or 5 in the realm of the possible.
  • Impacts may be severe depending on the exact proximity of the storm to Haiti and Jamaica.
  • Heavy rain, flooding, mudslides, and severe water impacts are possible, if not likely in portions of Jamaica, Haiti, and the Dominican Republic.
  • All areas in this region should be prepared for multiple days of high-end impacts.
  • The storm is not expected to threaten the US, but it will eventually turn north and northeast into the Atlantic, possibly impacting the Bahamas or Turks and Caicos Islands on the way out.

More to come on this, possibly later if time allows.