Shown on a topographic map are floodmark elevations and approximate areas flooded by Hurricane Frederic tides of September 12-13, 1979, along the Perdido River and Perdido Bay in the vicinity of the Alabama-Florida State line. Most of the damage in this area was due to minor flooding and high winds. Storm-tide frequency and records of annual maximum tides at Mobile, Alabama, since 1772, are presented. Offshore winds reached about 160 miles per hour. A wind-velocity of about 145 miles per hour was recorded near Dauphin Island, Alabama. (USGS)