Drivers struggled to make progress on the road because of the numerous potholes created by the heavy rainfall. A number of streets and underpasses were flooded.
The body of a man was found in an underpass in Unkapanı district.
The pedestrian underpass in Eminönü Square was filled with floodwaters and the shops in the square suffered great damage.
Many cars were stranded in traffic and rescued by fire engine crews. In one district, a parked car fell into a pit in the road created by the downpour.
As in the previous heavy rainfalls, the sea flooded the Üsküdar Square making it impossible to distinguish land from sea.
Flash floods briefly halted the ferry services connecting Asian and European sides of the city, while authorities warned citizens to be careful in the adverse weather conditions.
The General Directorate of Meteorology had previously issued a warning for on August 16, that Istanbul should expect very heavy rainfall.