Melissa bringing deadly and destructive rains to the Caribbean » Yale Climate Connections

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Tropical Storm Melissa has already brought death and destruction to the Caribbean, as the nearly stationary tropical storm begins to intensify. Melissa claimed its first fatality on Thursday night, when a falling tree killed an elderly man in Marigot, Haiti. Five others were injured in flooding in Haiti’s central Artibonite area, according to Haiti’s Civil Protection Agency.

As of 2 p.m. EDT Friday, Melissa’s low-level circulation was centered was about 230 miles (370 kilometers) southeast of Kingston, Jamaica, crawling east-southeast at a mere 2 mph (4 km/h). Data from the Hurricane Hunters showed that Melissa was finally beginning its long-forecast intensification, with sustained winds of 60 mph (95 km/h) and a central pressure of 997 mb (the 11 a.m. EDT numbers: sustained winds of 45 mph, central pressure of 1001 mb). Melissa’s disheveled, asymmetric structure is the result of moderate wind shear of 15-20 knots. Satellite imagery showed Melissa remained disorganized, with clumps of heavy thunderstorms focused on the east side of the center of circulation.

Heavy flooding from Melissa’s rains also brought chaos Thursday night to Santo Domingo, the capital of the Dominican Republic. The Santo Domingo airport recorded 7.00 inches (177.9 mm) of rain in the 24 hours ending at 8 a.m. EDT Friday, bringing their 3-day total to 11.80 inches (300.2 mm). Several personal weather stations in the city have recorded over 12 inches (304.8 mm) over the past three days. Blog commenter Reg R: posted this in the Eye on the Storm blog comments last night:

Good evening from Santo Domingo DR, city at an almost standstill, major flooding issues with unrelenting rain for long periods still today. Traffic interrupted in many areas and at a minimum, subway operating partially. The government ordered school and their offices closed tomorrow and that is the third day in a row, many businesses following. I have not ventured out but my power and internet have held. Social media ablaze with videos of the mess all over.

Figure 1. Probability of Melissa passing within 92 miles (150 kilometers) of a given location based on model forecasts, including the newest AI suite of models, issued at 0Z Oct. 24. Most guidance suggests a slow drift westward motion south of Jamaica, followed by a sharp turn to the northeast, carrying the storm over Jamaica and eastern Cuba early next week. (Image credit: Tomer Burg, Real Time Tropical Cyclones, via Michael Lowry)

Track forecast for Melissa

Melissa is trapped in a region of light steering currents, sandwiched between a high-pressure system to the southeast and one to the northwest. However, the models have increasingly been coming to a consensus that the competition between the highs will relax on Saturday, allowing the storm to track slowly westward just south of Jamaica on Saturday and Sunday. A sharp turn to the northeast into eastern Cuba is very likely early next week, but the timing and position of that turn is impossible to pin down, with steering currents so weak. There are many models showing a direct hit for Jamaica, but we’ve seen in the past how the high terrain of the island can play crazy tricks with the path of an approaching hurricane, steering them away from the island. This was particularly true in 2004, when Hurricane Ivan appeared on an inevitable course to plow directly over Jamaica, only to turn at the last minute and pass just 30 miles (50 km) south of central Jamaica as a Category 4 storm with 150 mph winds.

Regardless of the exact track, Melissa will bring multiple days of relentless torrential rains across the area to its north, to Jamaica, eastern Cuba, Haiti, and the Dominican Republic. The three-day rainfall forecast issued Friday by the National Weather Service (Fig. 2) depicts widespread amounts of 4 to 12 inches (100-300 millimeters) across eastern Jamaica and southern Hispaniola. Heavy rains could easily extend beyond that period until at least Tuesday – particularly across Jamaica, where precipitation totals from multiple models suggest that storm totals exceeding 24 in (610 mm) and localized amounts above 30 in (762 mm) are quite possible. Depending on Melissa’s exact track and strength, catastrophic flooding will be a very real possibility in one or more of these areas. Although the Cayman Islands lie to the west of Melissa’s expected path, they may experience significant flooding rains early next week as well, particularly Little Cayman and Cayman Brac islands.

Rainfall forecast for Melissa.
Figure 2. Rainfall forecast through 8 a.m. EDT Monday, Oct. 27, issued at 8 a.m. EDT Friday, Oct. 24. Rains of eight to 12 inches (200-300 millimeters, orange colors) were predicted for portions of Haiti, the Dominican Republic, and Jamaica, with some areas in excess or 16 inches (405 mm) over Jamaica and southwestern Haiti. (Image credit: NOAA/NWS/WPC via NHC)

Intensity forecast for Melissa

Very favorable conditions for intensification are expected from Saturday through Tuesday. The atmosphere is moist, and wind shear is predicted to fall by Friday night and be light to moderate, 5-15 knots, through Tuesday. Melissa will be traversing waters with sea surface temperatures (SSTs) of about 30 degrees Celsius (86°F), which are the second- to fourth-warmest SSTs on record for this time of year. Moreover, oceanic heat extends to great depths across the central and northwest Caribbean, which allows a slow-moving storm to strengthen without pulling up chillier water.

NHC is predicting that Melissa will become a hurricane by Saturday night and a major hurricane by Sunday night, peaking as a Cat 4 with 150 mph winds on Tuesday morning. However, Melissa may not get as strong as predicted if it approaches close enough to Jamaica to be disrupted by the high terrain of the island.

Kingston airport road damage from Hurricane Dean of 2007.
Figure 3. Kingston’s Palisadoes Road, which connects the airport with the mainland, covered with sand after Hurricane Dean of 2007. Dean caused approximately $510 million (2025 USD) damage to Jamaica. (Image credit: Jamaican government’s Planning Institute of Jamaica)

Storm surge risk for Jamaica: generally low

High winds and flooding rains are the chief risks of hurricanes in Jamaica. The island, in general, has low storm surge risk, since there are not a lot of low-lying coastal areas. One exception is Kingston’s Norman Manley International Airport, which occupies the Palisadoes tombolo, a narrow spit of sand and coral that connects the Lime Cay–Port Royal area to the mainland. When the airport was developed (initially during World War II, then expanded post-1950s), dredged material and imported fill was used to stabilize and elevate the low-lying coastal sands.

In 2004, Hurricane Ivan, which passed about 30 miles (50 km) south of central Jamaica as a Category 4 storm with 150 mph winds, caused total destruction of the sand dunes along the south side of the airport and inundation and blockage of the connecting road to the mainland. This led to the complete shutdown of the airport and the inability of Port Royal residents to access the mainland.

Hurricane Dean of 2007, which passed about 20 miles (35 km) south of central Jamaica as a Category 4 storm with 145 mph (235 km/h) winds, caused a similar impact, resulting in the shutdown of the airport. Since then, construction of the rock revetment along the south side of the airport has improved its capability to withstand a damaging storm surge.

Other storm-surge vulnerable places in Kingston include the Soapberry Wastewater Treatment Plant, Portmore Mall, Kingston Freeport Terminal, Nestlè Jamaica Limited, Jamworld Entertainment Center, the National Gallery of Jamaica, Petrojam Refinery, and Caribbean Maritime University. Not many residential areas are at risk of flooding in a Cat 3 storm, with the exception of a few low-lying areas on the west side of the city and in Port Royal (on the island connecting to the airport).

Jamaica’s costliest hurricane on record, Category 3 Hurricane Gilbert of 1988, inflicted damages of $1 billion ($2.7 billion 2025 USD), which was 26% of its $3.2 billion GDP at the time. Gilbert’s path from east to west along the length of the island did not generate a large storm surge along Jamaica’s south coast, where Kingston lies.

Kingston storm surge risk for a Cat 3 hurricane.
Figure 4. Storm surge risk map for Kingston, Jamaica for a Category 3 hurricane. Norman Manley International Airport is at risk of 3-6 feet (0.9-1.8 m) of flooding. (Image credit: NHC Storm Surge Risk Maps)

As far as Jamaica’s vulnerability to hurricane winds go, blog commenter Bitmap_7 posted this in the Eye on the Storm comments last night:

I wouldn’t be so concerned about residential infrastructure damage. The vast majority of homes in Jamaica are made with reinforced concrete, inside out. Windows and vaulted roofs are typically constructed to withstand extreme winds. Ever since Gilbert, most Jamaicans have been obsessed with Cat 5 proofing any new residential infrastructure. The biggest threat is the flood threat, but fortunately, there’s also lots of high ground in the country. Most of the damage will likely be to roads and farm land. This will set the government’s budget back, but Jamaica also has one of the highest net international reserves to gdp in the world for scenarios just like this. They have about 25% of their GDP as liquid cash for disasters just like this.

Track forecast for Melissa from Google's DeepMind model.
Figure 5. Probability of Melissa passing within 92 miles (150 kilometers) of a given location based on Google’s DeepMind ensemble model, issued at 6Z Oct. 24. A few of the model’s long-range scenarios show the possibility of Melissa or its remnants turning back toward the northeastern U.S. or Atlantic Canada late next week, but for now these probabilities remain low. (Image credit: Tomer Burg, Real Time Tropical Cyclones)

Long-range outlook for Melissa: the Bahamas at risk

After crossing eastern Cuba sometime Monday, Tuesday, or Wednesday, Melissa is likely to pass quickly through the southeastern Bahamas. This fast motion will limit the rains of the hurricane, but rainfall amounts of 5-10 inches (125-250 mm) are being shown over portions of the Bahamas by some model runs. Melissa will be weaker after its traverse of the rugged terrain of Cuba, but could still be at Category 3 strength in the Bahamas.

Later in the week, Melissa may be interacting with an extratropical storm predicted to form off the U.S. East Coast. The latest Google DeepMind ensemble forecast (Fig. 3) has a number of its members showing that this extratropical storm could sling Melissa (or its remnants) to the north or north-northwest, resulting in a landfall in Maine or Atlantic Canada. The details of the long-range track are highly uncertain, but we do have one historical example of a late October hurricane that hit Jamaica and eastern Cuba, and then was slung to the northwest into New Jersey — Hurricane Sandy of 2012.

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