A low-pressure system about 1,425 miles east-southeast of the eastern Caribbean Islands in the central Atlantic Ocean had a 60 percent chance of developing into a tropical cyclone over the next day or two.
The U.S. National Hurricane Center said in a report the system was moving west-northwest at about 15 miles per hour.
Most weather models project the system will reach the eastern Caribbean islands over the next five days.
Energy traders keep a close eye on storms that could enter the Gulf of Mexico and disrupt offshore U.S. oil and natural gas production or refinery operations along the coast, as well as the cleanup of the Gulf oil spill.
Commodities traders likewise watch storms that could damage agriculture crops such as citrus and cotton in Florida and other states along the coast to Texas.
Pricing of insurance-linked securities, which transfer insurance risks associated with natural disasters to capital markets investors and can be used to hedge other weather risk exposures, can also be affected by the path of a storm.