The South African Weather Service says a Yellow Level 4 warning for severe thunderstorms and excessive lightning is expected over the Highveld of Mpumalanga and northern Gauteng.
It says a Yellow Level 2 warning is in place for southern Gauteng, the eastern parts of the Free State, the south-western parts of Limpopo and in places over the Highveld and southern escarpment of Mpumalanga.
Storms are expected to continue across Gauteng into Tuesday , bringing thunderstorms and cooler temperatures. Senior Forecaster Samkelisiwe Thwala says parts of Gauteng remain at risk of damaging thunderstorms.