Hurricane Isaac has practically halted southeast of New Orleans and continues to dump heavy rain in Louisiana, a situation that is predicted to last all day and one that threatens to cause more flooding throughout the area, which on Wednesday marked the 7th anniversary of deadly and devastating Hurricane Katrina.

Isaac made landfall around 6:45 p.m. on Tuesday near the mouth of the Mississippi River, but it was heading directly for New Orleans, some 145 km (90 miles) northwest.

The center of the huge storm, which has a radius of some 320 km (200 mi.), was about 73 km (45 mi.) southeast of New Orleans and moving northwest at about 9 kph (6 mph) at 11 a.m. (1500 GMT) on Wednesday, the National Hurricane Center, or NHC, said in its latest bulletin.

The storm has maximum sustained winds of 120 kph (75 mph), the NHC said.

The NHC went on to say that Isaac has remained almost stationary for about the past hour but is expected to continue its slow movement to the northwest, meaning that its center technically could miss New Orleans itself and pass somewhat farther to the west through Louisiana.

Earlier in the day, the maximum sustained winds were measured at 130 kph (81 mph), with stronger gusts, but they lessened slightly in intensity over the course of the morning as the storm moved farther inland. With its current rate of movement, Isaac's center could be over the southern part of Arkansas by Friday.

A hurricane warning is in effect from east of Morgan City, Louisiana, up to the border between Mississippi and Alabama, a zone that includes the New Orleans metropolitan area, Lake Pontchartrain and Lake Maurepas.

It is also quite possible that tropical storm conditions could prevail from the Mississippi-Alabama border east to Destin, Florida, as well as along part of the northeastern coast of Texas.

In addition, tornado alerts are in effect in Louisiana and Mississippi, according to the National Weather Service, which confirmed that reports are that some levees have been topped by the storm surge causing significant flooding in Plaquemines Parish, where Isaac made landfall early Tuesday evening.

Isaac's slow movement means that its center could take hours to get to the area of Baton Rouge, the capital of Louisiana, but the relatively large diameter of the storm is causing a very wide area to be affected.

Electric utility Entergy and other power companies said that more than half a million people in the region were without power and warned that the number would increase as Isaac moves farther inland.

Intense rain and heavy winds are expected in New Orleans and the Louisiana coastal areas as the day progresses. EFE