The latest victims were reported in Rwanda, where officials from the northern region said floods killed 15 people and destroyed more than 500 homes since Wednesday.
In Sudan, the worst floods in living memory have left 64 people dead and displaced and affected several hundred thousand, mainly in the troubled south, according to the United Nations.
A cholera epidemic spread by floods has also killed at least 49 Sudanese in recent weeks, according to the World Health Organisation.
"The response is still ongoing... Most of the 200,000 plus people who were homeless at the end of August have by now been given shelter," Maurizio Giuliano, spokesman for the UN's Office for the Coordination of Humanitarian Affairs (OCHA), told AFP.
In neighbouring Uganda, the minister in charge of refugees and disaster preparedness said that 300,000 people were in need of humanitarian assistance.
"The situation borders a crisis," Musa Ecweru said.
He said nine Ugandans had died as a result of the floods, which he described as "a new phenomenon that we have not experienced for many years."
Kenya has also suffered from the downpours, a year after unprecedented floods displaced 700,000 people.
"We have activated our disaster response and the government and aid groups are providing food, shelter and medicine to those affected by the floods," government spokesman Alfred Mutua told AFP.
At least a dozen people have died in recent weeks as a result of the flooding in the east African nation.
The UN's food agency (WFP) and the Ethiopian authorities announced Friday they had launched a programme of food assistance targeting some 60,000 people among the most affected by the floods across the country.
"An estimated 183,000 people have been affected by floods this year... 42,000 of which were displaced and are in temporary shelters," Ethiopia's WFP spokeswoman Paulette Jones said.
"The figures are only estimated, they could rise once an assessment team concludes its study," she said.
"To date, the death toll from the flooding has reached 17 people, while some 4,000 head of livestock have been drowned or washed away, and 34,000 hectares of land has been damaged," a WFP statement also said.
Western and central Africa were not spared, as floods there have affected at least 500,000 people, according to the UN.
At least 33 people have died in Burkina Faso and 20 in Togo, according to figures released by the UN humanitarian affairs office in Geneva on Friday.
A Ghanaian government team that visited the devastated area in that country put the death toll at 18. Residents warned the toll might rise further.
The officials told reporters that 260,873 people in the west African nation had lost their homes to the floods.
Victims, who are already among the most malnourished people on the planet, are in dire need of tents, supplies, drinking water, medicine, mosquito nets, fuel and matches, OCHA spokeswoman Elisabeth Byrs said.
Torrential rains and floods have also taken a heavy toll on Nigeria, where 41 people have died in northern and central regions.
In Togo, non-stop rain over several days has washed away or damaged 22,000 hut homes, more than 100 bridges and 58 schools and colleges, along with 1,500 hectares (3,750 acres) of food crops and has left 34,000 people homeless.
The government has declared three days of national mourning for the victims and on Friday postponed the start of the school year, which was supposed to have started on September 17, by one month.
Last week, officials in Niger said around a dozen people had died in the country and more than 6,000 others had been affected by the heavy rains since July, and according Byrs one person has also been killed in Liberia.
Meteorologists in the Sahel countries that are better known for their punishing droughts have recorded virtually unprecedented rainfalls and predicted fresh downpours for Tuesday.