By September 17, the contact between a tropical wave and the end of a cold front created huge amounts of thunderstorms over the Bahamas and western Atlantic Ocean. An upper-level low over western Florida created more convection across the area, and on September 18 the system began moving towards Florida. Originally, the system was very disorganized, but surface pressures slowly went down across the area, with a weak low pressure area forming on September 19. A Hurricane Hunters aircraft was sent to fly into the system on September 20 reported an organized low and strong wind gusts in the storm as it moved into the northeastern Gulf of Mexico, along with little and disorganized thunderstorm activity. Convection slowly became better organized, with a well-defined rainband in its eastern half and irregular thunderstorm activity near the center. In spite of its bad organization, with a disorganized circulation and an upper-level low aloft, the National Hurricane Center started advisories on "Subtropical Depression Ten" at 1500 UTC on September 21 while it was located about 40 miles (60 km) south of St. Vincent Island, Florida, stating "the potential for additional development right along the coastline."