Hurricane Isaac's center has come ashore in southern Louisiana, about 75 miles southeast of New Orleans.
The center of the storm with top winds of 80 mph spun into Louisiana near the mouth of the Mississippi River.
The deputy director of the National Hurricane Center says Isaac's core will pass west of the city as it heads to Baton Rouge. Ed Rappaport says gusts could reach about 100 mph at times, especially at higher levels.
It's the eve of Hurricane Katrina's seventh anniversary and, while Isaac isn't as strong as Katrina, all eyes are on the levees that were strengthened after Katrina's deadly flooding.
The storm, which is 200 miles wide and moving slowly, could drop as much as 20 inches of rain in Louisiana and up to 12 inches elsewhere.