Hurricane Nate strengthened slightly on Saturday as it churned through the Gulf of Mexico, threatening to hit the U.S. central Gulf Coast as a Category 2 storm after it killed at least 25 people in Central America.

The outer bands of the hurricane were expected to batter parts of the U.S. Gulf Coast with tropical storm-force winds on Saturday evening, with the center of the storm forecast to make landfall overnight, said U.S. National Hurricane Center spokesman Dennis Feltgen.

It would be the third to hit the southern states this year.