(CNN) -- Officials in some Gulf Coast states spent the third anniversary of Hurricane Katrina on Friday gearing up for what could be the biggest threat to the region since Katrina hit in 2005.



New Orleans Mayor Ray Nagin attends a ceremony Friday honoring Hurricane Katrina victims.



Hurricane Gustav is poised to pass near or over the Cayman Islands on Friday night and over western portions of Cuba on Saturday. It may approach the U.S. Gulf Coast by Tuesday morning as a Category 2 or 3 hurricane, the National Hurricane Center said Friday.



"Today, on that third anniversary, we've got to be thinking about the future," Mississippi Gov. Haley Barbour said. "As we pray for the best, we're going to prepare for the worst,"



Barbour announced Friday that Hurricane Katrina victims living in government-issued trailers or mobile homes along his state's coast will begin evacuating this weekend to prepare for the Gustav's possible arrival.



The process will begin Saturday, with notices going out to people living in Federal Emergency Management Agency trailers or mobile homes, as well as people living in more permanent structures known as "Mississippi cottages," he said.  Watch the Gulf Coast states prepare for Gustav »



The evacuation will begin in Harrison and Hancock counties on Sunday morning, Barbour said. Evacuation in Jackson County will begin Monday.



About 4,300 families live in FEMA trailers or mobile homes, and 2,800 live in Mississippi cottages, the governor's office said. He said he would urge people living in privately owned mobile homes to evacuate as well.



President Bush declared an emergency in Louisiana on Friday, freeing up federal aid and allowing FEMA to coordinate relief efforts.



Louisiana Gov. Bobby Jindal has declared a state of emergency and urged residents to update their evacuation plans.



He said residents in certain southern parishes could be asked to leave Friday or Saturday. In Plaquemines Parish, where Hurricane Katrina roared ashore as a Category 3 storm days after its initial landfall in Florida, Parish President Billy Nungesser called for a mandatory evacuation beginning at noon Saturday.



Residents of the community of Grand Isle in Jefferson Parish were urged to begin voluntary evacuations Friday afternoon, and voluntary evacuations for Jean Lafitte, Crown Point, Barataria and areas outside the levee protection system are recommended beginning at noon Saturday, the parish said in a news release.



St. Bernard Parish, which was beginning transport Friday for those who would need assistance, said it expected to call a mandatory evacuation Saturday afternoon.



In New Orleans, which has yet to fully recover from Hurricane Katrina, Mayor Ray Nagin on Thursday urged residents living in FEMA units to make evacuation plans in case city officials order them to leave.  Watch Sean Callebs report on if New Orleans is prepared »



"Travel trailers are unsafe during heavy winds," he said. "As we continue to monitor and prepare for the possibility of Hurricane Gustav, I want all of our citizens to make certain they have a plan for leaving the trailers when advised to do so."



As of early this week, there were 2,829 FEMA trailers in Orleans Parish, the mayor's office said.



The city has designated 17 sites for people without transportation to board buses that would take them out of the city in the event of a mandatory evacuation. The city also arranged with Amtrak for more than 7,000 seats to evacuate the elderly by train, said Jerry Sneed of City Homeland Security and Emergency Preparedness.



Signs of mobilization were apparent at Louis Armstrong New Orleans International Airport, where nearly every departure gate had long lines of elderly people in wheelchairs. Rental car counters normally attended by tourists were filled with relief workers from the Red Cross and the Fire Department of New York's Disaster Assistance Response Team.



The DART team consisted of retired New York firefighters, jovial men with graying hair and larger waistlines. Many are volunteers assisting the Red Cross who were in New York during the September 11 attacks and wanted to give back.



The 40-member DART team of heavy-equipment operators, truck drivers and registered nurses was headed to Alexandria, Louisiana, to set up an evacuation shelter.



After the storm, the
What was the Grand Isle area of Jefferson Parish urged to do? What day will  evacuations  begin? Where was the disaster? what did the government declare what did barbour say What city did the disaster response teams arrive in? When will evacuations begin? Where did the Disaster response team arrive?
begin voluntary evacuations Saturday, New Orleans declared a state of emergency "Today, on that third anniversary, we've got to be thinking about the future," New Orleans this weekend Louis Armstrong New Orleans International Airport,
question: What was the Grand Isle area of Jefferson Parish urged to do?, answer: begin voluntary evacuations | question: What day will  evacuations  begin?, answer: Saturday, | question: Where was the disaster?, answer: New Orleans | question: what did the government declare, answer: declared a state of emergency | question: what did barbour say, answer: "Today, on that third anniversary, we've got to be thinking about the future," | question: What city did the disaster response teams arrive in?, answer: New Orleans | question: When will evacuations begin?, answer: this weekend | question: Where did the Disaster response team arrive?, answer: Louis Armstrong New Orleans International Airport,