UPDATE at 2:40 ET:
Here's the National Hurricane Center's update at 1:00 CDT on Monday:
...HEAVY RAINS AND FLOODING AFFECTING THE FLORIDA EAST COAST... SIGNIFICANT STORM SURGE THREAT EXPECTED FOR THE NORTHERN GULF COAST...
The storm surge for south-central Louisiana was expected to be 3 to 6 feet, the NHC said.
The latest information on the storm has it located about 300 miles southeast of the Mississippi delta and moving at about 14 mph. It was expected to make landfall as a Category 1 or Category 2 storm (winds up to 90 mph) around midnight Tuesday, according to the National Hurricane Center.
Louisiana Gov. Bobby Jindal warns that although Isaac is shaping up to be a weaker hurricane than Katrina was, its slow-moving nature could intensify the destruction.
"So the slow speed could actually create more damage as those forces accumulate," Jindal says.
According to Amy Jeffries of member station WRKF in Baton Rouge, nearly all the parishes in southeast Louisiana have declared states of emergency. Some low-lying areas are under mandatory evacuation orders.
Here's our earlier post:
Tropical Storm Isaac, fresh from spoiling the opening of the Republican National Convention in Tampa, was over the Gulf of Mexico today where it was forecast to strengthen to a hurricane before making landfall Tuesday south of New Orleans.
Isaac was expected to reach the New Orleans area seven years to the day after Hurricane Katrina hit the city on Aug. 29, 2005, killing 1,400 people in the state and racking up billions of dollars in damage.
The National Weather Service has issued a Hurricane Warning for an area east of Morgan City, La., to Destin, Fla., including the city of New Orleans.
Governors in Louisiana, Mississippi and Alabama have declared states of emergency in anticipation of the storm.
According to the New Orleans Times-Picayune website:
The forecast path places much of the New Orleans area in the eastern quadrant of the hurricane as it crosses the area, meaning the effects of storm surge also are likely to be moved westward into the New Orleans area. The center's forecast calls for that surge to be between 6 and 12 feet. The more westerly track also increases the chance that surge could have more impact on West Bank communities such as the Lafitte area and portions of Lafourche and Terrebonne parishes.
The storm is expected to drop an average of 8 to 12 inches of rain, with some areas getting as much as 20 inches, according to the newspaper.
UPDATE at 8:50 ET:
Brad Diehl, a meteorologist with the National Hurricane Center in Miami, tells NPR that the warm Gulf waters will fuel the storm as it heads toward the Louisiana coast.
"While there's always considerable uncertainty with the forecast track, at the moment they're expecting landfall in the continental U.S. to be roughly in the area just around New Orleans," Diehl says.
You can follow Isaac's track and read updates on the storm at the National Hurricane Center.