As Tropical Storm Isaac moved quickly through the Straits of Florida on Sunday morning, coastal communities in Florida issued mandatory evacuations and Republicans delayed the start of their national convention.

With sustained winds of 65 mph, Isaac lashed Cuba with strong winds and dumped rain on the island early Sunday. No major damage or injuries were immediately reported in Cuba.

Heavy rains were already falling in some parts of south Florida, where a tornado watch is in effect until 5 p.m. ET.

The outer bands of the storm extended as far as 205 miles from its center, which was roughly 80 miles southeast of Key West as of 11 a.m. ET.

Lee County, in southwest Florida, ordered residents in six communities, including the popular tourist spot of Fort Myers Beach, to evacuate, citing the possibility of significant storm surge.

The storm is expected to gain strength in the warm water of the Gulf of Mexico and become a hurricane by early Monday as it moves past the Florida Keys.

By late Monday afternoon or early evening, Isaac’s eye is expected to be west of Tampa. It is expected to make landfall again on Wednesday somewhere along the Alabama or Mississippi coast. By Wednesday the seventh anniversary of Hurricane Katrina Isaac could be a Category 2 storm with winds of at least 96 mph. The hurricane center said areas of the Louisiana coast from Morgan City east are under a hurricane watch. The watch includes New Orleans.

Florida Gov. Rick Scott said his state will be ready for whatever happens.

“This is a state that has dealt with hurricanes forever, he told reporters in Broward County. “We are a state that we know we have to get prepared for hurricanes.

Even so, the storm’s predicted track prompted officials to push back Monday’s scheduled start of the Republican National Convention in Tampa one day, hoping the move will make it safer and easier for delegates to attend.

In Key West, the southernmost point in the United States and likely the first part of Florida to be hit by Isaac, storefront windows were boarded up, while hotels were largely vacant even though no evacuation orders had been issued.

2012, KPLR