On July 6, the National Hurricane Center began monitoring a trough of low pressure as it moved from the Midwest over the Tennessee Valley. The National Hurricane Center expected the trough to emerge into the Gulf of Mexico, and potentially develop into a tropical cyclone within several days. From July 6-9th, the trough drifted southeastward across Tennessee, and southward across Georgia and the Florida Panhandle due to the steering influence of a ridge of high pressure over the Central United States. On July 9th, a broad area of low pressure developed across South Alabama, Georgia & the Florida Panhandle before the system entered the Gulf of Mexico. The low-pressure system, while still lacking a well-defined center of circulation, became a little better defined on the following day. As the system had a high potential of producing tropical storm conditions and storm surge along the coast of Louisiana within the next couple of days, the National Hurricane Center initiated advisories on Potential Tropical Cyclone Two at 10 AM CDT on July 10th. The system subsequently organized into a Tropical Storm Barry at 10 AM CDT on July 11th.

Tropical Storm Barry moved slowly westward, only slowly strengthening due to the tropical cyclone experiencing northerly wind shear through July 12th. This resulted in an abnormally structured storm, with most of the thunderstorms south of the center.