Amongst the worst affected areas were the sprawling slum districts which surround the city. The four victims of Saturday night's rainstorm were found in different parts of the city. She drowned while the brother survived. The girl's mother did try to save her daughter, but she couldn't swim and had to be pulled to safety. Following months of drought, Nairobi is now being swept by unseasonal rains.
Meteorologists say they are due to low pressure which has built up around Madagascar.
Last week two young sisters were swept to their deaths when they fell into a swollen stream near to their home.