The Gulf Coastal Plain is bordered by the Gulf of Mexico, a large body of water that significantly influences the region’s climate, ecosystems, and economy.

The Gulf's warm waters help create a subtropical climate, resulting in mild winters and hot, humid summers, ideal for agriculture and supporting a variety of plant and animal species. The Gulf Coastal Plain is known for its rich biodiversity, with wetlands, marshes, and estuaries that provide habitats for numerous species of fish, birds, and other wildlife. Economically, the Gulf of Mexico supports key industries such as commercial fishing, tourism, and oil exploration, making the region vital to both local and national economies. Additionally, the Gulf's coastal areas are popular destinations for recreation and tourism, attracting millions of visitors annually.