It had plenty of punch, however, when it rumbled ashore about 10 a.m. at the bayou hamlet of Cocodrie, an area sparsely populated by shrimpers and oil rig workers. It packed winds of 110 mph and brought with it the threat of a storm surge as high as 14 feet. Gustav also brought the threat of tornadoes.
Gustav looked to be on a trajectory to create a swath of destruction northwest through Houma, Morgan City and on to Lafayette. The area is largely abandoned, thanks to the evacuation of 2 million people, the largest evacuation in U.S. history.
One woman was killed in a car wreck in Louisiana, and three other individuals with critical health conditions died when they were evacuated.
Louisiana Gov. Bobby Jindal said Gustav is expected to deflate to a tropical storm by tonight. Nevertheless, he said Gustav has left nearly 500,000 people in Louisiana without power.
Jindal said it was still too early to know when evacuees would be able to return home, but added it probably would not happen by Tuesday as initially announced by Nagin.
"It's certainly too, too early to say that it's safe for them to start coming back tomorrow," Jindal said at a press conference at the state's emergency operations center in Baton Rouge. "Tomorrow's too early; we need to let the storm come through.
The governor said 85 percent of south Louisiana gas stations were out of fuel, and the industry cannot move fuel until the winds slow down. He called on President Bush to release fuel from the strategic oil reserve, calling it "absolutely critical."
Entergy, the major utility in Louisiana, reports 500,000 of their 1.2 million customers in Louisiana have lost power, and the number continues to grow. Cleco Corp., which has 273,000 customers in the state, said the number of customers without power was at 50,000 and growing.
In Baton Rouge, 60 miles north of New Orleans, and the state's operating center for first responders, Mayor Kip Holden said two hospitals had lost power, but assured residents the situation was under control.
"This is not a doom and gloom scenario. For residents going through this for the first time, everything is going OK. We are seeing some things that are the same as Katrina, but we are getting through them," Holden said. "A lot of people are dependent on us right now. I assure them we are in control."
Mayor Tim Matte of Morgan City, about 80 miles west of New Orleans, told ABCNews.com that a mandatory evacuation had succeeded in clearing out 75 percent of the population and the city was protected by a 24-foot seawall, with levees surrounding the city.
Matte predicted that the area of Houma, a major supply base for the oil industry, would be hardest hit.
Houma Parish President Michel Claudet told ABCNews.com that the lightly protected area was being hammered by 95 mph winds that were strong enough to peel back the roof of the parish firehouse and knockout power to their emergency services center.
Claudet said their biggest concern is that the area has no hurricane levees, and is protected only by drainage levees that are not prepared to handle storm surges from a Category 2 hurricane.
"All we have are drainage levees. We've got no hurricane protection. Drainage levees are not the same as storm protection levees," he said.