The first day has already been postponed. But if Isaac prevents the thousands of delegates from gathering at the convention hall, not to worry: Republicans will still have a presidential nominee come November.
With more than 50,000 people expected to descend on Tampa, the idea that the quadrennial party celebration could be a no-go — or even somehow obstructed by a weather event — is a fairly terrifying possibility for Republicans who have been planning the GOP confab for over a year.
And it's problematic on other fronts, too: Until Mitt Romney is officially nominated as the GOP candidate for president, for example, he can't access his sizable general election funds or even be officially certified so that states can begin printing his name on ballots.
Party officials have already considered this. In the worst-case scenario where the Republican convention simply can't physically occur, the party can still nominate Romney and vice presidential contender Paul Ryan through another process that would be determined by the Republican National Committee.
RNC rules state that, in the event the convention cannot be held as planned, the RNC can outline and vote on another method of its choosing under which to conduct the presidential nominating process.
"If the Republican National Committee determines that the national convention cannot convene or is unable to conduct its business either within the convention site or within the convention city, then and only then, the roll call for nomination for President of the United States and Vice President of the United States shall be allowed to be conducted according to procedures authorized by the Republican National Committee," the rules say.
If that situation arose, those familiar with the rules say, the 168-member RNC could vote on specific procedures for a roll call: the roll call could be done electronically or via telephone, or the RNC could choose another meeting place for the thousands of delegates.
Most RNC members are already in the Tampa area for meetings held over the last week, so they could likely determine a backup plan in person. If those members had to evacuate because of adverse weather conditions, they could make a final decision on how to nominate Romney and Ryan over the phone.
The party's rules for nomination roll calls were changed in the lead-up to the 2004 convention in New York as a post-9/11 precautionary measure, said a senior Republican involved in the planning.
"There is no such thing as canceling," said RNC communications director Sean Spicer. "In terms of the business of the RNC, the number one thing is obviously nominating — officially nominating — Mitt Romney as our presidential candidate and Paul Ryan as our vice presidential candidate."
This is a scenario the party was aware of when it chose Tampa as its convention site during the height of hurricane season, and it's a contingency for which both state and party officials have been preparing.
Jonathan Martin contributed to this report.