Tropical Storm Threatens Tampa

Tropical Storm Isaac is gaining strength over warm waters and may become a Category 2 hurricane as it approaches Tampa just in time for the start of the GOP convention.

Forecasters with the National Hurricane Center said a newly-formed tropical storm could threaten the site of next week's Republican National Convention by early next week. Storm warnings were issued Tuesday for portions of the eastern Caribbean Islands after Tropical Storm Isaac formed in the Atlantic Ocean. As of 5 p.m., Tuesday, Isaac had maximum sustained winds of 40 mph. Isaac is moving to the west at 17 mph. On its present track, it is expected to pass over the Windward Islands on Wednesday, moving into the Caribbean Sea.