A low-pressure system in the Gulf of Mexico has formed into Tropical Storm Karen.
Data from an Air Force hurricane hunter plane shows the system, located in the southeastern Gulf, is producing winds up to 60 mph.
Karen could be at or near hurricane strength by Friday.
A hurricane watch was put in effect Thursday from Grand Isle, La., to Indian Pass in the Florida Panhandle – an area that includes Mississippi’s entire coastline.
The system is expected to move due north, with a cold front shifting it slightly to the east, taking it across the Florida panhandle early next week.
That track would mean the Tampa area would be on the outskirts of the storm, bringing increased rain chances into the start of the work week.
The storm is expected to produce heavy rains in Cuba and the Yucatan peninsula today and Friday.
The Mississippi Emergency Management Agency is telling people in or near the three coastal counties to prepare for tropical weather by late Friday or early Saturday.
MEMA spokesman Greg Flynn said Thursday that people who live in flood-prone areas should think about where they’ll go if ordered to evacuate. He said south Mississippi residents, particularly along the coast, should make sure they have supplies in case power goes out.
Information from The Associated Press was used in this report.