Steve Slack didn’t heed the evacuation warnings before Hurricane Katrina swamped New Orleans, and ended up suffering with thousands in the Superdome waiting for buses to take them out of town.

He wants to avoid that if another big storm hits the city. But with gas prices at $4-plus a gallon, Slack, 68, who is retired and on a fixed income, doubts he’ll make it far in his 1994 Chevrolet pickup truck.

“I’ll probably stay until they run me out,” Slack said. “I don’t know where I could get the extra money it would take to evacuate. I just barely stretch it for what we need now.”

With memories still fresh of the chaotic evacuation from New Orleans as Katrina neared in August 2005, officials want people to be ready to move if a major hurricane threatens, but they worry gas prices, expected to remain at or above $4 through hurricane season, may keep many motorists from filling up when an evacuation is ordered. That could mean they’ll run out of gas, block highways and keep others from getting out of harm’s way.

Their suggestion: start saving now.

“With gas prices going up almost daily, you may want to start putting away $2 or $3 every week in your disaster kit,” said Kay Wilkens of the Red Cross. “So you’ll have enough money to fill the tank if you need it.”

In Mississippi, residents are being advised to set aside $75, although evacuees can expect to spend much less time on the road than south Louisiana residents, said Mike Womack, executive director of the Mississippi Emergency Management Agency. That’s partly because many in Mississippi can head straight inland while the greater expanse of coastal Louisiana means more distance to travel on highways that are routinely clogged even in sunny weather.

Still, high-priced gas will affect evacuations, Womack said.

“I think the big impact is that some people may say they are not going to evacuate,” Womack said. “Or they’ll try to evacuate without enough gas in their vehicle. Either way will cause problems.”

When residents filled up to evacuate before Katrina, gasoline was selling at $2.30 a gallon, said AAA Louisiana spokesman Don Redman. As interstate highways clogged with thousands of vehicles, motorists ran out of gas, slowing the evacuation.

“We had traffic issues then, and certainly people running out of gas was one of them,” said Lt. Doug Cain of the Louisiana State Police.

State Police plans call for troopers with extra gas and tow trucks to be placed along evacuation routes, but adding a gallon of gas to a car may not get them far.

“I get about 11 miles to a gallon,” said Bob Conroy, 52, a salesman. who lives in the New Orleans suburb of Metairie. “That’s nothing, and if I sit in traffic and idle it’s less than that. It’s killing me. I don’t want to think about evacuating in that jam.”

Preparing for evacuations is inherently stressful, said Phillip Griffin, professor and chief of the psychological section at LSU Health Sciences Center. Adding the worry about expensive gas ratchets up the tension, he said, especially for those who went through Katrina.

“Those of us who have done it before know you can’t always determine how far you will have to go or how long it will take,” Griffin said. “It’s staggering for someone with a good income to fill up the tank. How will those on fixed incomes or working minimum wage jobs deal with it?”

It’ll be tough, said Kathleen Whalen, psycho-social program manager for the domestic emergency unit of Save the Children.

“If they’re told to evacuate, the only way that will be possible is to crowd together in cars,” Whalen said. “What you’ll see is piling way too many people in a car, so that there are no safety precautions, no seat belts. It will be very dangerous.”

Saving $3 a week, as officials suggest, would only give evacuees $15 a month, and provide less than four gallons of gas.

For some, finding an extra $3 is tough.

“I don’t have any plan for evacuating,” said Rochelle Cook, 43, of New Orleans, who is unemployed. “I have a car, but it needs tires and I can’t afford to put any money away for gas. I can barely get gas to get around and do what I need to now.”

Shirley Dangerfield, who is 63 and retired, evacuated New Orleans as Katrina approached with her two daughters and six grandchildren in an SUV. Since then, they’ve financially struggled to rebuild their homes.

“Everything has been very expensive,” she said. “And now we have gas prices way up. Everything cost a lot of money, and evacuating will too. I just have to believe God will make a way for us.”

Cook and Dangerfield may have no choice but to find some way out.

New Orleans officials do not plan to operate any hurricane shelters and the Superdome will not be a “shelter of last resort.” The plan calls for a mandatory evacuation order 72 hours before a Category 3 or stronger hurricane is expected to hit.

“Katrina taught me a whole lot about reserving things,” Dangerfield said. “But you can’t reserve what you don’t have. And after Katrina, I don’t have a lot more than I do have, especially money.”