NEW ORLEANS - Hurricane Isaac made a second landfall in Louisiana early Wednesday with strong winds and torrential rains, providing the first real test of flood control systems and emergency services in New Orleans on the seventh anniversary of Hurricane Katrina.

The storm first hit Port Fouchon at 3:15 a.m. EST, around 60 miles southwest of New Orleans, unleashing damaging 80 mile-per-hour winds and drenching coastal cities in Louisiana and Mississippi, reports USA Today.

Moving at an estimated speed of 8-miles-per-hour, Isaac could dump up to 20 inches of rain in some areas and cause major flooding, adds CNN. According to the hurricane centre, Mississippi and southeastern Louisiana could see peak surges of 12 feet.

Yet all eyes are on the New Orleans levee system, which was rebuilt and reinforced at a cost of $14 billion after it failed when Katrina struck in 2005.

Isaac will also be a test for the preparedness of the city's officials, exactly seven years after one of the costliest natural disasters in the U.S. history, in which some 1,800 died.

“We are officially in the fight, and #nola is on the front lines”, tweeted New Orleans Mayor Mitch Landrieu.

Isaac was upgraded from tropical storm to Category 1 hurricane earlier Tuesday.

Isaac killed 29 people when it hit Haiti and the Dominican Republic but left little damage in Key West, Florida, reports The New York Times.