As rain started to fall on this city’s empty streets Sunday night nearly 2 million people from the Louisiana coast evacuated. Painfully aware of the failings that led to more than 1,600 deaths during Katrina, this time officials moved beyond merely insisting tourists and residents leave south Louisiana. They threatened arrest, loaded thousands onto buses and warned that anyone who remained behind would not be rescued.

Late Sunday, Gov. Bobby Jindal issued one last plea to the roughly 100,000 people still left on the coast: "If you’ve not evacuated, please do so. There are still a few hours left."

Louisiana and Mississippi temporarily changed traffic flow so all highway lanes led away from the coast, and cars were packed bumper-to-bumper. Stores and restaurants shut down, hotels closed and windows were boarded up. Some who planned to stay changed their mind at the last second, not willing to risk the worst.

"I was trying to get situated at home. I was trying to get things so it would be halfway safe," said 46-year-old painter Jerry Williams, who showed up at the city’s Union Station to catch one of the last buses out of town. "You’re torn. Do you leave it and worry about it, or do you stay and worry about living?" There were frightening comparisons between Gustav and Katrina, which flooded 80 percent of New Orleans. There was no doubt the storm posed a major threat to the partially rebuilt city and the flood-prone coasts of Louisiana and southeast Texas.

Mindful of the potential for disaster, the Republican Party scaled back its normally jubilant convention – set to kick off as Gustav crashed ashore. President Bush said he would skip the convention altogether, and Sen. John McCain visited Jackson, Miss., on Sunday as his campaign rewrote the script for the convention to emphasize a commitment to helping people.

The nation’s economic attention was focused on Gustav’s effect on refineries and offshore petroleum production rigs. The combination of prolonged production interruptions, such as occurred when Katrina and Rita damaged the Gulf infrastructure, could trigger rising prices.

Billions of dollars were at stake in other wide-ranging economic sectors, including sugar harvesting, the shipping business and tourism. The Mississippi Gaming Commission ordered a dozen casinos to close. Forecasters said Gustav could strengthen slightly as it marched toward the coast. At 11 p.m. EDT Sunday, the National Hurricane Center said Gustav was centered about 220 miles southeast of New Orleans and was moving northwest near 16 mph. It had top sustained winds of 115 mph, and was likely to stay a Category 3 storm when it made landfall west of New Orleans. Category 3 storms have winds between 111 mph and 130 mph. Rain started falling in New Orleans before sunset, and tropical storm-force winds had reached the southeastern tip of the state.