Tropical Storm Lee began crawling northward just off the Louisiana coast on Saturday evening after blasting the United States' Gulf Coast with strong wind and heavy rain, drenching the region and knocking out power to thousands.
A tropical storm warning has been extended to include parts of the Florida Panhandle. The warnings now stretch from Sabine Pass, Texas to Destin, Fla.
The storm remains offshore, about 88.5 kilometres south of Lafayette, La.
Forecasters at the National Hurricane Center said the storm had been stationary for a few hours on Saturday.
Lee's maximum sustained winds dropped from 97 kilometres per hour to 75 km/h later in the evening.
Entergy, a major utility company in the area, reports that more than 35,000 customers in and around New Orleans were without power as Lee churned towards land. Outages have also been reported in central Louisiana and Mississippi.
While Lee approaches the Gulf coastline, tropical storm warnings are in effect from Mississippi to Texas. Flash flood warnings have also been extended along the Alabama coast and into the Florida Panhandle.
Forecasters said they expect the storm to begin a slow and erratic path to the north and northwest and make landfall later Saturday afternoon or evening.
Small bayou towns like Jean Lafitte were evacuated as water lapped up on doorways.
The storm is expected to hit parts of the region with up to 50 centimeters of water over the Labour Day weekend.
Forecasters predict up to 37.5 centimeters of rain will fall in southern Louisiana alone.
Lee formed in the waters off Louisiana on Friday and soon began dumping rain over the Gulf States including Mississippi and Alabama. The wet journey is to be expected, reports The Associated Press, as the storm's slow speed is giving rain clouds more time to drench anything in its path with water.
Patchy downpours caused some low-lying streets to flood in New Orleans on Saturday, but well-placed pumps were quick to suck up the water and send it into the nearby Lake Pontchartrain.
Lee's storm surge so far had not penetrated levees along the coast, National Weather Service forecaster Robert Ricks said.
Even as the storm's outer bands pelt Gulf States with rain, the region's storm-experienced residents say Lee hasn't lived up to the legacy of previous storms.
"This is mild. Things could be worse," New Orleans resident Malcolm James told The Associated Press on Saturday.
James, a federal investigator, had to be airlifted away from his home by helicopter after Hurricane Katrina devastated New Orleans in August 2005.
"It's a lot of rain. It's nothing, nothing (compared) to Katrina," he said.
Lee is expected to make landfall on the central Louisiana coast late Saturday and then turn east toward New Orleans. There, it will provide the biggest test of the region's rebuilt levees since Hurricane Gustav struck on Labor Day 2008.
Lee clears Gulf oil fields, cuts production
So far, the storm force has been felt mainly on the Gulf of Mexico oil fields. About half the Gulf's normal daily oil production has been cut as rigs were evacuated, though oil prices were down sharply Friday on sour economic news.
Federal authorities said 169 of the 617 staffed production platforms have been evacuated, along with 16 of the 62 drilling rigs. That has reduced daily production by about 666,000 barrels of oil and 1.7 billion cubic feet of gas.
The National Hurricane Centre said on Saturday that the storm's centre was moving north-northwest at 6 km/h. Lee is expected to cross the Louisiana coast by Saturday night and pass into the southern portion of the state on Sunday.
The storm comes less than a week after Hurricane Irene battered the Caribbean and the U.S.'s eastern seaboard, killing more than 50 people.
Lee is the 12th named stormed of the Atlantic hurricane season.
With files from The Associated Press
