An already warm Gulf of Mexico will once again be heating up this summer thanks to one of the Atlantic Ocean’s fastest and warmest currents—the Loop Current—which carries warm water from the Caribbean Sea up past the western tip of Cuba and into the Gulf. There, huge swirling rings of deep warm water the size of Maine will break off from the primary current and wander westward through the Gulf, providing a potent heat source that could cause hurricanes travelling overhead to rapidly intensify. “I’ve heard these ring-shaped eddies—and the Loop Current from which they detach—described as ‘high-octane fuel’ for hurricanes,” says Heather Furey, a research specialist at WHOI. “Where the rings are in relation to the path of a hurricane can have a significant effect on the storm’s intensity.”Hurricane Rita in 2005 is a case in point. Before slamming into the Gulf Coast that year, the storm passed directly over one of the Loop Current's eddies, which caused it to explode into a monster Category 5 hurricane before making landfall.