Isaac lumbers inland, carrying more rain and flooding dangers

NEW ORLEANS -- Hundreds of thousands of weary Gulf Coast residents remained without power Thursday as Tropical Storm Isaac slowly headed inland, posing new threats of heavy flooding. Already, rising waters have forced scores of residents from their homes.

“Even though Isaac is no longer a hurricane, the life-threatening hazards from storm surge, inland flooding and tornadoes are still ongoing,’’ Dennis Feltgen, a meteorologist and spokesman at the National Hurricane Center, told the Los Angeles Times. “We don’t want anybody in that area that’s being impacted to let their guard down.’’

Isaac is expected to become a tropical depression by Thursday night.

The center of slow-moving Isaac, which was over Louisiana on Thursday morning, is expected to move over Arkansas on Friday and southern Missouri on Friday night. “But its impacts will be felt in those areas well before the arrival of the center,’’ Feltgen said.

Tommy Jackson, a spokesman for the Arkansas Department of Emergency Management, said Thursday morning that rain from Isaac had begun falling in the southern part of the state.

The state has been suffering from a severe drought, he said, and officials are worried about the potential for flooding because the ground is so hard.

“We’re watching and waiting,’’ he said. Much of the state is under a flash flood watch.

In Plaquemines Parish, south of New Orleans, officials were considering breaching a levee to lower water levels; on Wednesday, floodwaters had forced the dramatic rescue of residents stranded in attics and rooftops. Authorities planned to survey the levee by boat on Thursday.

“We’re still getting a six-foot storm surge from the gauge on the southern side of Lake Pontchartrain,’’ said Feltgen, “and we’re getting a storm surge value of about five feet at Waveland, Miss. So it’s not over.’’

Flooding led to new evacuations Thursday morning in Slidell, La., where officials said that pumping stations were “unable to pump the water out as quickly as it is rising.’’ Some businesses and homes had taken on as much as two to three feet of water, officials reported.

President Obama on Wednesday night declared major disasters in Louisiana and Mississippi, clearing the way for federal aid.

On the road to Plaquemines Parish, a long line of cars snaked down Belle Chasse highway for the one open gas station. Police cars patrolled parking lots of grocery stores, apparently to deter looters.

Numerous roads were closed due to flooding. It was expected to take days before electricity is restored. New Orleans and other communities were under a dusk-to-dawn curfew Wednesday night.

Isaac from start to finish is expected to dump as much as 25 inches of rain over Gulf Coast communities.

“As the storm continues to progress through Arkansas and Missouri, we could see rainfall amounts of four to eight inches, including in St. Louis,’’ Meghan Evans, an Accu Weather meteorologist, said in an interview Thursday.

On Thursday morning, at a discount store in New Orleans, where about 50 people were lined up, customer David Guys complained about the seemingly endless rain.

“This is worse than Katrina,’’ he said. “Katrina came through, did her damage and was gone. This just won’t go away.’’

Even as he spoke, more rain fell. Guys complained about the power outage. “You can send robots to Mars and you can’t turn the power on…. It was just a little Category 1 storm.’’

Posted on the door to the store was a cardboard sign, “We are inside and armed,’’ a message aimed at deterring the kind of looting that occurred after Katrina.

Susman reported from New Orleans; Simon from Washington.

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tina.susman@latimes.com

richard.simon@latimes.com