The careful planning that has gone into the most tightly orchestrated event of the GOP’s quadrennial calendar was being overwritten by Mother Nature on Sunday, as officials scrambled to adjust the proceedings and schedule of the Republican National Convention in the face of Tropical Storm Isaac.

As the storm battered the Florida keys and showed the potential of turning into a Category 2 hurricane, it appeared that the convention city would be spared the brunt of its force. It was expected to make landfall Tuesday or early Wednesday somewhere on the Gulf Coast, much of which was under a hurricane watch.

But Isaac was nonetheless wreaking havoc with the convention schedule, having already delayed Monday’s opening by a day, and continuing to upend the travel plans of many of the estimated 50,000 delegates, media and others planning to attend.

Romney campaign strategist Russ Schriefer told reporters Sunday evening that all of Monday’s headline speakers had been rescheduled for later in the week and other daytime speakers had been dropped from the program or their speeches will be shortened. The program will begin at 7 p.m. instead of 8 p.m., but there are no other plans to cancel or shift events, he said. “We’re obviously monitoring what is going on with the weather,” Schriefer added.

Among those who cancelled or put a hold on their appearances at the convention were the governors of four states likely to be most heavily affected by the storm: Rick Scott of host-state Florida; Louisiana’s Bobby Jindall, Mississippi’s Phil Bryant and Alabama’s Robert Bentley.

What did not get interrupted, however, was the campaign combat. Leading Republicans took to the airwaves to give a preview of the message they plan to deliver at the convention.

Former Massachusetts governor Mitt Romney, who will be officially anointed as the GOP nominee this week, attempted to shore up his support among women voters in an interview on Fox News Sunday. He accused President Obama and the Democrats of exploiting recent controversies, including the one that Rep. Todd Akin, the Republican Senate candidate in Missouri, created with his comments about rape.

“It really is sad, isn’t it, with all the issues that America faces, for the Obama campaign to continue to stoop to such a low level,” Romney said.

Obama, in an interview with the Associated Press, had accused Romney of taking “extreme positions that are very consistent with positions that a number of House Republicans have taken. And whether he actually believes in those or not, I have no doubt that he would carry forward some of the things that he’s talked about.”

Indeed, the rough weather itself became a metaphor as the Republicans warmed up for their convention. “You know, tidal waves often follow hurricanes. And in November, a tidal wave is coming,” thundered tea party favorite and U.S. Senate candidate from Texas Ted Cruz, at a pre-convention gathering sponsored by the Faith and Freedom Coalition, an organization that seeks to mobilize evangelical voters.

Emergency management officials had plans in place to evacuate the city, which is prone to flooding. Heavy rains could bring three to five feet of water.

Scott said that Florida was prepared for the storm — and the convention. “We’re a state that knows how to do hurricanes. We don’t like them, but we know how to do them,” Scott said on CNN’s “State of the Union.” “We do hurricanes well and we do hospitality well, and this week we’ve got to show both sides.”

Democrats, who had planned a strong counteroffensive, scrapped some of their plans, too, including a Sunday afternoon news conference with the Democratic National Committee chairwoman and local officials. Vice President Biden also postponed plans to campaign in Florida on Monday and Tuesday.

In 2008, Republicans had to cancel a day of events in St. Paul as Hurricane Gustav headed toward landfall in the Gulf. With the party experiencing a more serious repeat of that episode, scrutiny has fallen on the selection committee and former RNC chairman Michael Steele for picking Florida, a state prone to severe weather.

The 12-member committee scouted several cities, including Phoenix and Salt Lake City, but ultimately decided on Tampa because it was the most prepared to handle a convention that costs some $40 million to host.

Cindy Costa, a South Carolina delegate who was on the selection committee, said that the other cities seemed equivocal during the selection process, and that Florida got the nod in the end on a unanimous vote.

“Everybody was thrilled, obviously,” Costa said. “But in the back of your mind you know [severe weather is] a possibility. It’s just one of those imponderable things that you can’t know.”

Even with the most severe weather headed elsewhere, convention planners are mindful of the schedule and the specter of holding a big event when another region of the country is dealing with an emergency.

Monday’s theme was to be “We Can Do Better,” highlighting the country’s rising debt and lingering joblessness. Scheduled speakers included House Speaker John A. Boehner (Ohio), former Florida governor Jeb Bush, former Arkansas governor Mike Huckabee, South Carolina Gov. Nikki Haley and Sen. Rand Paul (Ky.). The roll-call vote that would make Romney’s nomination official, which was planned for Monday night, is now scheduled for Tuesday.

Heading into Tampa, Romney had been trying to build on the momentum following the largely successful rollout of Rep. Paul Ryan (Wis.) as his vice presidential running mate. But his task of winning over moderate voters became more challenging last week as the Missouri Senate candidate’s comments on “legitimate rape” and abortion — as well as Romney’s quip Friday about Obama’s birth certificate — highlighted views at the fringes of the Republican coalition.

Romney’s advisers had planned an elaborately choreographed convention aimed at presenting him as a successful businessman and compassionate family man.

Rosalind S. Helderman and Rachel Weiner contributed to this story.