Senegalese President Macky Sall has activated an emergency aid plan after a seven-hour downpour caused widespread floods.
Water Minister Serigne Mbaye Thiam told national television that more rain fell on a single day on Saturday than the country would usually see during three months of the rainy season.
"This is an exceptional rainfall. We registered 124 millimetres of rain. This is the cumulative rain we get during the whole rainy season from July to September," Thiam said.
At least one person was reported missing due to the floods in the central region of Kaolack, said Aissatou Ndiaye, mayor of Ndiafatte.
Senegal's private radio station RFM said three children died due to the floods, two in the southern Casamance region and one in the northern Kanel region.
In Guediawaye district close to Dakar, volunteers raced to scoop out flood water and debris from a heavily flooded health centre.
"More than five communities use this health centre and we are desperate and we don't know what to say and ask for help. We have seen no mayor, no councillor, no firefighters. We have seen no one," resident Momodou Baye Fall told Reuters.
According to forecasts by Senegal's meteorological agency ANACIM, more thunderstorms and rains were expected on Sunday across most of the country.
Heavy rains have been recorded in the Sahel regions of West and Central Africa in the past week including in Niger, Nigeria, Chad and Cameroon, leading to devastating floods that have killed dozens and displaced thousands of people.
In Niger's capital Niamey, a levee on the right bank of the Niger River burst on Sunday following heavy rains, forcing families in several neighbourhoods to evacuate, authorities said.
(Reporting by Diadie Ba and Zohra Bensemra in Dakar and Boureima Balima in Niamey; Writing by Bate Felix, Editing by Angus MacSwan and Sonya Hepinstall)
