During the second week of July, a trough of over the southeast United States drifted slowly south-southeastward, producing some scattered afternoon thunderstorms as it went. A few days later, on July 9, this anomalous motion brought it into the extreme northeastern Gulf of Mexico, where more consistent convection began to flare up. Weak steering currents allowed the system to meander west-southwestward and it gradually organized, developing a broad circulation. By July 10, a clear low-level center had formed, but it was displaced well to the northeast of the mid-level circulation. Moreover, the strongest thunderstorms were actually located over southeast Louisiana, where significant flooding occurred before the tropical disturbance had even been classified.
Finally, on July 11, improvements in organization prompted the naming of Tropical Storm Barry, located now nearly due south of the Mississippi delta. Even after naming, however, dry continental air pushing in from the other restricted cloud cover to the southern portion of the tropical storm, and several small low-level vortices were evident on satellite imagery. This disorganized hampered Barry's intensification. Nevertheless, the pressure fell appreciably over the next day and aircraft reconnaissance indicated that the system's maximum winds steadily increased to strong tropical storm strength by July 12.
Meanwhile, Barry took a turn north of west around the edge of the mid-level steering ridge and began to move toward Louisiana. Even by the afternoon of July 12, however, the northern semicircle remained very dry, so few effects were felt over land even with the system less than 100 miles offshore. Despite its unconventional structure, Barry steadily strengthened through landfall. It peaked as a category 1 hurricane with 75 mph winds and a pressure of 993 mb on July 13 as it crossed the central Louisiana coastline around noon local time. The slow movement of the system resulted in only a gradual weakening trend and prolonged heavy rainfall, especially just east of the landfall point. Nevertheless, Barry weakened to a tropical storm shortly after landfall and a tropical depression on July 14 as the center of circulation pushed further inland. Upper level winds out of the north kept most of the precipitation over water even as the center moved away, sparing inland areas from more severe flooding. Soon after, the storm became extratropical over the midwest.
The above image shows Hurricane Barry near landfall, with most of the northern half of the circulation exposed.
Barry originated from a non-tropical disturbance over the southeast U.S.
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