New Orleans ? Remnants of Hurricane Ivan swung back into the Gulf of Mexico and developed into a tropical storm Wednesday, prompting warnings in Louisiana and southeastern Texas.

The storm was expected to make landfall sometime tonight.

The remnants kicked seas up several feet, posing a threat to fragile barrier islands and their beaches in both states. The storm also forced some offshore oil and gas crews to head home.

A tropical storm warning was issued from the mouth of the Mississippi River in Louisiana west to Sargent, Texas.

Ivan was upgraded to a tropical storm after sustained winds were measured near 40 mph. The National Hurricane Center in Miami said the storm could strengthen before landfall.

After hitting Florida last Thursday as a hurricane, Ivan weakened and broke apart, with most of the storm heading north to drench southern and mid-Atlantic states. A slice of the storm turned southward, however, and dropped up to 5 inches of rain Monday on Florida before moving into the Gulf.

Meanwhile, meteorologist said Hurricane Jeanne could strike the United States by this weekend. It was too soon to tell where, but the Hurricane Center warned people in the northwest and central Bahamas and along the southeast U.S. coast to beware of dangerous surf and rip currents kicked up by Jeanne in the coming days.

At 10 p.m. CDT Wednesday, Jeanne was centered about 485 miles east of Great Abaco Island in the Bahamas. It was moving west-southwest at about 5 mph and was expected to turn west today.