Tampa has been given the all-clear signal for Isaac, the tropical storm expected to grow in strength to a hurricane over the Gulf of Mexico. But the problems for the GOP as they try to hold their signature unveiling of Mitt Romney to the nation may have just begun.

The tropical storm headed through the Gulf of Mexico today, up to the Gulf Coast, where it’s expected to make landfall somewhere along a 300-mile stretch of coastline sometime Wednesday.  That will be the 7th anniversary of the landfall of Hurricane Katrina in the same region. Fortunately, the forecasts call for a strengthening to only a Category 1 hurricane and not a Category 2, as previously predicted.

However, the storm is large; it has already caused destruction when it went through Haiti, killing 19 and wrecking many of the tent cities, where 800,000 Haitians implausibly still live after the big earthquake there in 2010.

The storm has picked up some of the strength that degraded when it passed through land in the Caribbean, and should reach hurricane-force winds by tomorrow. The size of the storm means that the most damage could come from the amount of rain it will drop on the low-lying coastal areas, perhaps as much as 20 inches. Inland flooding remains a major concern, as it was in Vermont and north Atlantic areas during Hurricane Irene, which hit about a year ago to the day.

The storm surge could reach 6-12 feet and has been described by the National Hurricane Center as “life threatening potentially.” Areas outside of New Orleans have been put under mandatory evacuation.

The governors of Alabama, Louisiana and Mississippi declared states of emergency as a hurricane warning went into effect for a roughly 300-mile stretch of the Gulf Coast in four states from Louisiana to the Florida Panhandle.

“Tonight is when the conditions will start to go downhill” ahead of landfall by Tuesday night, Knabb said.

This has already had a political impact for the leaders in the states affected. Governor Bobby Jindal has pulled out of the Republican Convention, joining Florida Governor Rick Scott (the Republican Governors of Alabama and Mississippi were not scheduled to speak). Jindal had a speaking slot in the 8:00 hour on Wednesday.

More important than that, viewers tuning in for the convention can expect a split-screen of Republicans whooping it up over small government plans in Tampa, while government evacuation and emergency efforts persist to the west in the Gulf. The hope is that all emergency efforts go smoothly and there’s no bad news to report. But thanks to the response to Katrina in 2005, the optics of a Gulf hurricane are now a net negative for the GOP. They will have to deal with that juxtaposition in imagery.

Probably the best news source for the storm in the next couple days will come from Dr. Jeff Masters at Weather Underground.

And the next word you hear from anyone in Republican politics or the media about the relationship between the frequency and intensity of storms like these and climate change will be the first.