East Africa has been experiencing heavy rains, experts say, with floods forcing families from their homes.
The Indian Ocean Dipole, the Indian Ocean's equivalent of the Pacific Ocean-based El Nino, is at its strongest since 2006, the regional trade bloc of eight East African nations known as the Intergovernmental Authority on Development said on Friday.
"In this state, warm moist air flows westwards inland increasing the likelihood of higher rainfall over East African countries," it said.
In the town of Beledweyne in central Somalia, a river overflowed and about 10 people died when a boat capsized trying to rescue stranded residents, residents said.
"I am still stranded in a hotel in Beledweyne," Mohamed Nur told Reuters from the town. "A relative of mine was among those who died after the boat capsized this week."
Halima Abdullahi, a mother of three, told Reuters by phone that floodwaters had trapped her family and they were desperately awaiting rescue.
"The floods are too much and the river which broke from many parts has not yet been repaired," she said. "We do not know what to do."
A tropical storm next week is expected to worsen the floods. Rains are forecast to continue until the end of the year and humanitarian organizations are warning of waterborne diseases and mass displacement.
"Higher than usual rains are expected to continue through November and December, leading to more floods and conditions for disease," the International Rescue Committee said in a statement. "Recovery from these weather conditions may take years."