The Red Cross says at least 15 people have died in Kenya as floods swept away dozens of houses.
Entire villages in the north of the country have been inundated, forcing residents to head for higher ground. Swathes of farmland have been devastated.
The El Niño weather phenomenon has also helped cause flash flooding in Somalia and Ethiopia, leaving tens of thousands displaced.
Climate change is having a major impact in the Horn of Africa which is experiencing frequent extreme weather events.
Since late 2020 the region has been suffering from its worst drought in 40 years.