People in the eastern and central parts of Limpopo and Mpumalanga are advised to take precautions against inclement weather.
A tropical storm in the Mozambique channel looks set to make landfall any time from Thursday night.
Forecaster at the South African Weather Service Dipuo Tawana on Tuesday told The Citizen the tropical storm was also expected to affect people in the northern parts of Gauteng, including Hammanskraal.
Tropical storms are associated with strong winds and heavy rainfall, which also leads to flooding, Tawana said.
“Based on our information, the storm is expected to be severe,” Tawana said.
“We are expecting wind speeds of between 80 and 90km/h.”
The rest of Gauteng can expect just a 30% chance of isolated showers and thundershowers.
Tawana said the storm was expected to die down from Saturday.
The tropical storm comes barely months since the weather desk had forecast heavy rain for the Mpumalanga, Limpopo and Gauteng provinces.
“Much-needed rainfall, as long as not harmful will be welcomed by many,” said the weather services forecaster.