It has already proved deadly – and it is gathering strength.
Wilma is the 12th hurricane of the Atlantic season.
By the time it crosses from the Caribbean Sea into the Gulf of Mexico on Friday – heading for Florida – it is expected to have grown into a powerful Category 4 storm, with winds of over 200 kilometres an hour.
Haiti has already paid a heavy price, with up to 10 people killed in mudslides triggered by Wilma. In Cuba, thousands have been evacuated as weather conditions worsen.
People have also been forced to flee in Jamaica, amid flooding and landslides that blocked roads and damaged homes in low-lying areas.
Wilma is also threatening Honduras and Nicaragua, compounding the woes of Central America, which is still recovering from Hurricane Stan.
Since records began, there have only been 12 hurricanes in an Atlantic season once before, back in 1969.