From the NHC Preliminary Report on Frederic
Forming from a tropical wave on the west African coast late on August 27th, there was little to distinguish this storm from any other. But by the morning of August 30th, Frederic gained hurricane strength and began barrelling for the Carribean Sea. Frederic made landfall in Alabama on the evening of September 12th over Dauphin Island. Though 135 mph was measured on the bridge from Dauphin Island, central Alabama only experienced gale force winds.
Over a dozen tornadoes were reported with the storm, mainly near the Gulf Coast, but they resulted in no deaths and only minor property damage.
Rainfall amounts of 8 to 12 inches were fell from Pascagoula to Mobile Bay with 4 to 6 inches over parts of eastern Mississippi, western Alabama northwestern Florida and northward into Tennessee. 2-4 inches fell along the track all the way to New England, but there were no reported cases of flooding with Frederick any where in the United States.