As part of its five Cooperative Agreements with the U.S. EPA, the Southern Oxidant Study (SOS) Science Team has promoted the development and application of a unique regional air quality modeling system, referenced as Seasonal Model for Regional Air Quality (SMRAQ). The SMRAQ modeling system was developed using the Environmental Decision Support System (EDSS). An initial thirty-day SMRAQ simulation performed for July 7, 1995 to August 5, 1995 showed an average error of eight-hour average ozone ranging from 20 to 25 percent. Based on the analysis of the initial simulation, modifications are being made to the SMRAQ model and a full four-month simulation of the summer of 1995 will be carried out during the spring of 1998.