Isaac weather
News reports for Tropical Storm Isaac appear on screens ahead of the Republican National Convention at the Tampa Bay Times Forum. - 

Jeremy Hobson: Hurricane Isaac is hammering Louisiana this morning. And at last count, more than 430,000 customers were without power.

The storm has also shut down more than 90 percent of the Gulf of Mexico's oil production, which has sparked the old question of whether it's time to open the nation's Strategic Petroleum Reserve to head off any potential effect on the economy.

Marketplace's Mark Garrison reports.

Mark Garrison: There’s a 50/50 chance President Obama will crack open the reserve, according to Fadel Gheit, who tracks energy for Oppenheimer and Co.

Fadel Gheit: Nice try, but it might not work.

That’s because it’s an oil reserve, not a gasoline reserve. More than 40 percent of oil refineries are in the Gulf. Many are shut down now. If refiners aren’t processing oil into gas, prices at the pump are unlikely to go down much. Oh, and it’s an election year.

Gheit: Unfortunately, both sides will take very cheap shots.

Republicans will criticize the move as a political ploy. Democrats will say they’re trying to help drivers in a tough economy. In New York, I'm Mark Garrison, for Marketplace.

Follow Mark Garrison at @GarrisonMark