TAMPA, Fla. -- A Republican National Convention already slowed by Tropical Storm Isaac faces new threats Tuesday from the storm, as its trek up the Gulf Coast could make it tough for the party to stage the kind of joyous, momentum-building event that often gives candidates a big boost.

Mitt Romney plans to arrive in Tampa on Tuesday, ahead of schedule as the convention hold its first full day of activity – and as his wife makes a prime-time speech about him. His trip to the convention city two days before he’s to accept the Republican nomination was announced late Monday.

The party is scheduled to adopt its platform and conduct the roll call of the states to nominate Romney, a former Massachusetts governor, for president and Rep. Paul Ryan of Wisconsin for vice president. The evening’s agenda features Ann Romney and New Jersey Gov. Chris Christie, the keynote speaker.

Romney is scheduled to travel to Indianapolis on Wednesday to speak to the American Legion, then return to Tampa to give his acceptance speech Thursday night.

Tampa’s weather calmed Monday as the storm bypassed the Tampa Bay region – where the Republicans curtailed Monday’s planned convention opening out of an abundance of caution. But the storm still threatens to hit elsewhere. Hurricane warnings were issued for parts of the northern Gulf of Mexico coast, including New Orleans, Biloxi, Miss., Gulf Shores, Ala., and Pensacola Beach, Fla., areas devastated by Hurricane Katrina’s march through the region seven years ago this week.

Many convention eyes, as well as news media attention, were on the storm Monday.

Isaac was forecast to make landfall along the Louisiana, Mississippi or Alabama coast as a Category 2 hurricane, with winds of about 100 mph, late Tuesday or Wednesday. Tropical storm force winds, at 39 to 73 mph, could reach parts of the states Tuesday. Evacuations started in New Orleans-area parishes.

The storm is expected to move slowly through Louisiana and Mississippi on Thursday before losing tropical storm status and heading into Arkansas by Friday. Fifteen inches of rain could fall in some areas.

A direct hit on New Orleans would be a fresh test of political acumen for both major political parties .

President George W. Bush was criticized for the federal government’s response to Katrina’s aftermath. Mindful of that experience, Republicans abbreviated the program on the first day of their 2008 convention after Hurricane Gustav threatened the Gulf, postponing an appearance by Bush, even though the convention was in St. Paul, Minn.

This year, Monday’s convention session was shorted to a 10-minute affair that conducted no major business. Delegates seemed wary of any more big changes to the convention they’ve been eagerly anticipating for months.

“The world goes on,” said Jim Ayala, a Henderson, Nev., home inspector.

“We have a responsibility to go ahead and get Gov. Romney’s message out,” said A.J. Matthews, a retired police officer from Tampa. “We might take a more somber approach.”

Speakers can still offer contrasts to President Barack Obama, added Brock Cordeiro, a Dartmouth, Mass., sheriff’s aide. “We just may have to cut back on the cheerleading,” he said.

Convention organizers were being circumspect about their plans.

“We are continuing to go ahead with our program of Tuesday, Wednesday and Thursday. We’ll see what happens over the next few days,” said Russ Schriefer, a top Romney strategist. “Obviously our first concern,” he said, is the people in the path of the storm.