A severe drought that has parched the Caribbean since May 2026 was fueled by human-induced climate change, according to a recent study.
The rapid analysis was released by World Weather Attribution (WWA), a global network of researchers who analyze the influence of climate change in extreme weather events.
In the Caribbean, the wet season runs from May-June to November-December. The researchers found that rising global temperatures due to human-induced climate change reduced rainfall during the early wet season, between May and July, by approximately 6% in Jamaica and 9% in Puerto Rico. They estimated this drop in rainfall has made extreme dry spells 40% more likely in Jamaica and 30% more likely in Puerto Rico, compared to the pre-industrial climate that was 1.4°C (2.5°F) cooler.
“This three-month rainfall event was, in today’s climate, approximately a 1-in-50-year event in Puerto Rico, and a 1-in-30-year event in Jamaica,” Theodore Keeping, a climate researcher at Imperial College London and coauthor of the scientific report, said during a virtual WWA press briefing.
The impacts of the drought have accumulated across the region. San Juan International Airport in Puerto Rico registered its driest April-to-August period in 70 years, with precipitation 64% below average , according to Paul Miller, an atmospheric scientist at the University of Georgia, U.S., during the WWA briefing.
The study added that critically depleted reservoirs forced Puerto Rican authorities to implement 48-hour rotating water rationing, affecting 180,000 water service customers in the capital region. Meanwhile, Jamaica placed seven parishes under strict water prohibition orders, outlawing non-essential water uses.
“Drought impacts look much different in islands like Puerto Rico than they do in more continental settings,” said Miller during the briefing. “The lack of large rivers, big reservoirs, ample groundwater supply … drought impacts can accumulate especially quickly in these landscapes.”
According to research cited in the study, the Caribbean loses an average of 46% of its water to grid leakages, peaking at 60% in Puerto Rico, highlighting that infrastructure issues can compound the water crisis.
“Outdated water infrastructure, especially vulnerable drinking water systems with high leakages worsen shortages during droughts,” Karina Izquierdo Rofriguez, a vulnerability expert with the Red Cross Red Crescent Climate Centre, said during the briefing. “Persistent exposure to climate hazards such as tropical storms can weaken infrastructure and coping mechanisms intensifying susceptibility to additional extreme events.”
Rodriguez further added that factors “such as pre-existing inequalities, infrastructure quality, land use patterns, and population density frequently influence whether a hazard escalates into a disaster or remains a manageable event.”
Imperial College London’s Keeping said their models showed that the North Atlantic Oscillation, a natural pattern of winds and atmospheric pressure over the North Atlantic, was the primary driver of this year’s early wet season drought in the Caribbean, but El Niño will exert a strong drying influence as the year progresses.
Banner image: A woman lifts a jug she filled with water from a tanker truck amid rationing caused by drought, in the Cupey sector of San Juan, Puerto Rico, Aug. 5, 2026. Image by AP Photo/Alejandro Granadillo.
