Flooding was expected in places in Gauteng, Mpumalanga, Limpopo, the Free State and Kwazulu-Natal, the SA Weather Service said on Saturday.
Heavy falls of rainare expected in places in the southern parts of Mpumalanga and the northern part of KwaZulu-Natal, forecaster Edwin Thema said.
"We can expect flooding in KwaZulu-Natal, Limpopo, Mpumalanga and Gauteng on different days," he said.
"Any significant rain would cause flooding. We have also seen trees falling everywhere because the ground is wet."
No serious incidents
Meanwhile, Johannesburg emergency services said they had not received notice of any serious incidents on Saturday.
"We are still on high alert and are monitoring the critical river areas," spokesman Robert Mulaudzi said.
"Motorists need to be vigilant because the roads might be flooded and damaged due to the rain over the last few days."
He also said parents should make sure children stay away from river streams and drainage systems.
Read: Floodwater threatens health
Tshwane emergency services spokesman Johan Pieterse said there had been no incidents in Pretoria on Saturday because the rain "comes and goes". He said they would continue to monitor the rivers.
Motorists were urged to avoid low-lying bridges and to seek alternative routes when driving in rainy weather conditions.
Meanwhile, disaster relief has been rolled out on Saturday, to relocate 16 families at the Monotomosetlha informal settlement, near Coligny, the office of the North West premier said.
Disaster management protocol
Premier Thandi Modise urged municipalities to adhere to the disaster management protocol.
She also urged municipalities to alert the provincial Disaster Management Centre about all flooding incidents.
"Communication and proactive engagement among role players is key to mobilise capacity and support to manage all disaster incidents," Modise said in a statement.
Thema said more rain was expected in the North West.
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