Spike hailstones covered parts of Gauteng in a white blanket after a thunderstorm swept across the city on Monday afternoon.

The South African Weather Service (SAWS) had warned of possible severe thunderstorms which could cause localised flooding in parts of Gauteng, the North West, Mpumalanga, the Free State, KwaZulu-Natal and Limpopo.

Saws forecaster Lehlohonolo Thobela had told TimesLIVE there was also a possibility of hailstorms in parts of Gauteng on Monday afternoon.

"Flash floods and heavy rainfall are expected in the afternoon and might cause flooding in low-lying areas and informal settlements," Thobela had said.

Thunderstorms with showers and isolated showers are expected to continue for the rest of the week in most parts of the country.

Storm Report SA said spike hailstones are usually caused by slow movement through a storm's updraft and collide with other hail stones.

"They collide, stick together and refreeze forming the conglomerate of mini hail stones into bigger lumpy hailstones," it said.

Take a look at the snaps below:

More storms expected

The stormy weather is expected to continue on Tuesday, with Gauteng Weather warning residents to brace for even more thunderstorms and hail.

"The South African Weather Service issued a warning for a high likelihood of severe thunderstorms in Gauteng on Tuesday. Heavy rain, localised flooding, hail and strong winds possible in places," it said.

Vox Weather also issued an alert, saying similar weather can be expected on Tuesday and Wednesday.

It said the possibility of severe thunderstorms in Limpopo, Gauteng, Mpumalanga and the Free State will intensify as widespread showers and thundershowers move over the central and eastern parts of South Africa.

"On Tuesday and Wednesday, scattered thundershowers will continue over northern South Africa.

"Weather models are currently picking more than 80mm; [it] could accumulate until Friday over large parts of the Bushveld, along the Eastern escarpment, northern Gauteng and the highveld regions of Mpumalanga."