Tropical Storm Debby has formed in the Gulf of Mexico, heading north with sustained winds of 50 mph. It was expected to turn west toward south Texas by midweek.

Richard Rude, meteorologist for the National Weather Service, said the system is drifting north between the Yucatan Peninsula and Louisiana coast.

“Right now most of the computer modules have it moving to the north and turning to the west before it reaches Florida, but these things are rather unpredictable,” he said.

According to the Associated Press, this is the first time since 1851 that four storms have formed before July.