On August 9, an area of convection formed just south of Jamaica in association with a trough of low pressure. The system moved west-northwestward, and by August 10, the system had a broad surface trough with a little shower activity. Convection increased on August 11, and by August 12 the contact between a tropical wave and an upper-level low in the area resulted in a large area of disorganized thunderstorms extending from the western Caribbean Sea into the central Bahamas. Upper-level winds slowly became more helpful for development, and on August 13 a large low pressure area formed about 90 miles (145 km) north-northeast of Cancún, Quintana Roo. Late on August 14, a NOAA Hurricane Hunters plane that flew into the system reported a small circulation center, but at the time was not well-defined enough to begin tropical cyclone advisories. However, deep convection was kept near the increasingly organizaing center, and at 0300 UTC on August 15 the National Hurricane Center named it as Tropical Depression Five about 425 miles (685 km) southeast of Brownsville, Texas.