TAMPA, Fla. - President Obama sought to assure the nation Tuesday that his administration has fully prepared for Tropical Storm Isaac, which could soon become a hurricane and hit the Gulf Coast as early as Tuesday night.

Appearing in the Diplomatic Room of the White House, Obama said that emergency response workers have been on the ground for a week in preparation for a storm on the seventh anniversary of Hurricane Katrina.

But he warned Gulf Coast residents living in the path of the storm to take extra precautions.

"We're dealing with a big storm, and there could be significant flooding and other damage across a large area," he said. "Now is not the time to tempt fate, now is not the time to dismiss official warnings. You need to take this seriously."

Obama will now head to Ames, Iowa, for the first stop on a campaign-trail trek through the Hawkeye State, Colorado and Virginia. Obama is looking to take some of the political spotlight away from the Republican National Convention in Florida.

Isaac has already forced convention organizers to cancel the first day of festivities here Monday and reshuffle the convention into a three-day affair. They have not ruled out further cancellations if the weather batters the Gulf Coast in coming hours.

As Obama looked to showcase preparations for the storm, at least one governor in the storm's path was questioning the president's commitment to Gulf Coast residents.

Republican Louisiana Gov. Bobby Jindal sent a letter to Obama Monday questioning why the president didn't go beyond declaring a state of emergency in Louisiana.

"Unfortunately, your limited declaration does not provide for reimbursement of expenses that the state is taking to prepare for the storm," Jindal said. "The state's expenditures for emergency protective measures are already approximately $8,000,000 and exceed the State of Louisiana's threshold when making a request for a major disaster declaration."