Torrential rains had claimed more than 66 lives by Sunday evening, authorities said. The rains continued without signs of slowing, including in the capital, Nairobi.
Parts of the city have been flooded, as have extensive areas where river levels have risen and submerged large tracts of land.
Many bridges have been damaged and major roads have been closed.
The Red Cross gave an example of the consequences after one of the organization's operations: eleven people were rescued when they were at risk of drowning in a minibus that had become stuck as water levels rose, according to the BBC.
Authorities are now urging residents in low-lying areas to evacuate as the risk of new flooding increases with continued rain.
