threatening new orleans' fresh water supply. maria: isaac is forcing the coast guard to halt all ship traffic moving into and out of tampa bay, right now. that order too effect two hours ago. it includes cargo and cruise vessels. the coast guard says there are no exceptions unless "there is a significant change in this storm's path or the intensity." the coast guard is also involved in securing the waters around the convention area. we have seen them up and down the river outside of the building we are watching the area bridges. they have a lot on their hands between the two events. >> now a like look at the convention center floor where the republican a party is getting final preparations done in the arena where the hockey team plays in tampa. the threat of isaac forcing the party to cram four days of convention over vents into three days including the release of the party platform.