A tropical wave moved off the coast of Africa on August 19, accompanied with spiral bands of convection around an area of low pressure. A large circulation quickly developed once it reached the Atlantic Ocean, and the system organized into Tropical Depression Four late on August 19 while located 345 mi (555 km) southeast of Cape Verde. Initial forecasts predicted for great intensification, including one forecast for the depression to strengthen to a hurricane within three days. However, the depression remained disorganized, and slowly intensified to attain tropical storm status on August 22.