Galveston's Flag Warning System uses color-coded flags to alert beachgoers to water conditions and potential hazards. Green indicates calm conditions, yellow advises caution, red signals out-of-the-ordinary conditions, purple warns of marine life dangers, and orange indicates environmental concerns. The flags are posted along Seawall Boulevard and at lifeguard towers during the summer months. Before heading to the beach, visitors should check the Galveston Beach Patrol's real-time updates on beach conditions for their safety.