Tampa, and the Republican convention, may have dodged a meteorological bullet.

But even as Tropical Storm Isaac veers off further down the Gulf Coast, defying earlier predictions, the fallout still threatens to inflict heavy damage on Mitt Romney’s big national moment.

It’s not just that Monday looks to rain on the parade of the thousands of journalists and delegates assembling here. Nor is it the quick decision by GOP officials to pull the plug on Monday’s events, bumping big-name speakers such as Mike Huckabee and losing a valuable day in the spotlight.

The real problem comes Tuesday, when the convention opens and television news is faced with a split-screen dilemma: politics or weather?

Take a tip from a veteran media-watcher. Don’t bet against the weather.

Isaac is expected to make landfall on Tuesday. And even though Tampa will have been spared the brunt, we could be looking at a Category 2 hurricane barreling into New Orleans, potentially on the seventh anniversary of Hurricane Katrina.

Executive producers will have to choose between that dramatic tableau of potential death and destruction and the canned proceedings of a scripted convention and rather predictable speeches.

Let’s be generous and say media organizations spend half their time on the storm and half on the events in Tampa. That, after being rained out on Monday, represents a huge squandered opportunity for Mitt Romney.

This was to be his week, the chance to redefine himself in the national consciousness as a warm, concerned, church-going family man, and to introduce Paul Ryan as more than a green eyeshade budget-slasher. Romney can never get this time back. Next week will belong to Barack Obama and the Democrats in Charlotte, and after that a breakneck general election largely dominated by the three debates.

All because the weather took a bad turn.

The irony is that if Isaac had come along last week, it would have gotten a fraction of the media attention with no convention to inject a compelling story line.

Now I could make a case that the media have a collective responsibility to provide deep coverage of the quadrennial conventions that, however choreographed, help voters make their presidential decision. A storm, despite its impact on the affected communities, is more of a fleeting event.

But that rubicon was crossed long ago. Romney was grumbling about the broadcast networks’ failure to cover the first night of his convention even before Isaac forced its cancellation, and some conservatives are complaining about media bias. Never mind that ABC, CBS, and NBC took the same approach four years ago, or that Obama bowed to television reality by trimming his convention to three days.

If the storm continues to steal the spotlight, it could limit whatever bump Romney gets from his convention. And that could render him the storm’s biggest victim.