After hitting Florida on Sept. 16 as a hurricane, Ivan weakened and broke apart as it traveled north, drenching southern and mid-Atlantic states before returning to sea. Its remnants then swung southward, growing slightly as it traveled over warmer waters.
The regenerated storm was expected to make landfall in the Gulf of Mexico on Thursday night, and could bring 50 mph winds and 5 to 10 inches of rain.
Ivan already has kicked seas up several feet, posing a threat to fragile barrier islands and their beaches in both states, and forced some offshore oil and gas crews to head home.
"It looks like from what they told us earlier that probably we'll see some minor coastal flooding, beach erosion sometime tomorrow," said Tesa Duffey-Wrobleski, Galveston County's emergency management coordinator.
In Louisiana, Cameron Parish leaders were keeping an eye on the storm, but hadn't issued any evacuation orders yet, said Emergency Preparedness Director Freddie Richard Jr. The swampy parish is located in the southwest corner of the state.
"We're just advising people in low-lying areas in Cameron Parish to prepare to move to higher ground if the tides come up," he said.
The National Hurricane Center issued a tropical storm warning for the Gulf of Mexico shoreline from the mouth of the Mississippi River in Louisiana west to Sargent, Texas.
Ivan was upgraded to a tropical storm Wednesday evening after sustained winds were measured near 40 mph. The Hurricane Center said the storm could strengthen before landfall.
Forecasters said the center of the storm was poorly organized and was about 295 miles southeast of the upper Texas coast at 10 p.m. Wednesday. Ivan was moving toward the west-northwest at about 13 mph.
The first round of Ivan and its remnants were blamed for at least 52 deaths in the United States and 70 in the Caribbean. Much of the destruction was caused by flooding.
Also Wednesday, North Carolina officials warned coastal residents they may have to evacuate as early as Sunday if Hurricane Jeanne continues on its projected path.
Jeanne sits several hundred miles east of the Bahamas, but is already causing high swells, dangerous rip currents and some erosion problems in North Carolina.
Several meteorological models used by the National Hurricane Center show the storm making landfall somewhere between Georgetown, S.C., and the Cape Fear River early next week. Other models show Jeanne affecting the Savannah, Ga., area.
The busy storm season continues with Hurricane Karl in the mid-Atlantic moving toward Northern Europe, and Tropical Storm Lisa gathering off the northeast coast of South America.
Hurricanes do occasionally reform — sometimes with deadly results. In 2002, Hurricane Isidore dropped to a tropical wave before regaining hurricane strength and killing four people in Louisiana. A year earlier, Hurricane Chantal was a tropical depression, weakened to a tropical wave, then became a hurricane, killing two people in Trinidad.