Isaac Churns in Caribbean, Threatens RNC

As winds picked up in the Dominican Republic, Tropical Storm Isaac continues to churn across the Caribbean on Thursday. Winds of 45 miles an hour - forecasters said the storm - which had weakened slightly - could gain strength and become a hurricane within a day. Hurricane warnings were in effect for the Dominican Republic and Haiti. Computer models put the storm on track to hit off the coast of Florida by Monday - the first day of the Republican National Convention in Tampa. Florida governor Rick Scott. ...