St. Elmo is an unincorporated place located in Alabama, USA. It is within Mobile County at exactly 7 miles north of Bayou La Batre and the Mississippi Sound. It is 10 miles of Grand Bay to the east along U.S. Highway 90. St. Elmo took its name from the book St. Elmo, authored by Augusta Evans Wilson. A farming community which was served by the L&N Railroad. St. Elmo Elementary School is part of Mobile County Public School System located in St. Elmo. It has Zip code 36568 and Area code 251. The elevation is 135 feet. St. Elmo is in Central (CST) (UTC-6).