Tropical storm Isaac expected to reach hurricane strength, Florida braces

SAN JUAN, Puerto Rico (AP) - Puerto Rico and the U.S. Virgin Islands are braced for torrential rains today.

Tropical Storm Isaac is churning up waves as high as 10 feet. And it's threatening to become a hurricane that could take a shot at Florida just as Republicans gather for their national convention in Tampa.

Forecasters say Isaac will likely turn into a Category 1 hurricane by tomorrow as it nears the Dominican Republic and Haiti. It's expected to weaken a little while heading over their island and Cuba, then possibly move on toward Florida as a hurricane by Monday.

As Isaac makes its approach to Puerto Rico, flooding is already reported in eastern and southern areas of the island.

The National Hurricane Center says the storm is centered about 200 miles south-southeast of Puerto Rico with winds of 40 miles an hour, and and it's moving west at about 13 miles an hour.

Dominica's disaster coordinator says that island was spared the "full brunt" of the storm, which passed over last night. No damage or injuries have been reported and the airports and seaports have reopened.