Was the one of the costliest hurricanes to ever hit the U.S. Gulf Coast. Damage estimates vary from $1-3 billion, with variations due to inadequate reporting of private insurance claims as well as lack of hard data on uninsured damage. FEMA, which had been established only three months before Frederic hit, was the focal point for nearly $250 million in federal aid for recovery, $188 million of which went to Alabama.
Anywhere from 250,000 to 350,000 people in the U.S. were evacuated in advance of Frederic. Its sustained winds were clocked at 125 mph (200 km/h), classifying Frederic as a category 3 storm. Its intensity at landfall, based on barometric pressure readings of 27.94 inches of mercury (946 mb or 94.6 kPa), rank it in the top 25 among U.S. hurricanes in the 20th century. Storm tides of eight to 12 feet above normal were reported from Pascagoula, Mississippi to western Santa Rosa Island, Florida. Five people were killed by the storm and its aftermath.
Frederic, only the second hurricane given a masculine name, originated as a tropical depression off the west coast of Africa on August 29. It developed an eye on September 1 and briefly weakened from impact of Hurricane David. It passed over Puerto Rico and the Dominican Republic, then suddenly turned northwest during the afternoon of September 5. It passed just west of Santo Domingo on September 6. It weakened again, eventually regaining tropical storm strength 100 miles (160 km) east of Cuba's Isle of Youth on September 9. It regained hurricane intensity a day later, as it was off the western tip of Cuba, and headed towards the Gulf Coast.
It came ashore on September 13 with winds reaching 145 mph (over 230 km/h) at Dauphin Island Bridge, near the mouth of Mobile Bay. An hour later, it hit the coastline just west of Mobile, Alabama, near the state's border with Mississippi.
Frederic continued north and northeast, downgraded to a tropical storm near Meridian, Mississippi. It crossed the southwest corner of Pennsylvania on September 14. Its remnants moved very rapidly northeastward through Pennsylvania, New York, and western New England during the day. By evening, it exited from northern Maine; it still managed to bring more than three inches (80 mm) of rain to southern Québec.
Frederic developed off the African coast on August 27, briefly became a hurricane on September 1, and then weakened to a tropical depression just north of Haiti. Frederic began to strengthen on September 7 and regained tropical storm intensity on September 9 near western Cuba. Frederic then turned to the north northwest with increasing forward speed for the next 60 hours. The eye passed over Dauphin Island,AL on the 13th. The highest winds recorded on Dauphin Island were 120 mph with gusts to 145 mph. Tides of 8 to 12 feet above normal were reported in the hurricane warning area from Pascagoula, MS, to western Santa Rosa Island, AL. Storm tides were 12 feet at Gulf Shores, AL.
Advance preparedness activities by Alabama authorities kept the death toll to five with estimates of 350,000 persons evacuated from the threatened area.