Heavy rains that can lead to localised flooding is expected along the southern and western parts of KwaZulu-Natal as well as the south-eastern parts of the Eastern and Western Cape on Sunday, the South African Weather Service has warned.

In addition, severe thunderstorms were expected over the Highveld and escarpment areas of Mpumalanga, it advised in a statement.

"An intense cut-off low is expected to affect the Western Cape on Sunday into Monday. The public is advised that heavy rain and flooding is expected over the Garden Route, Overberg District and Breede River Valley as well as along the Wild Coast," it said.

In Gauteng, cloudy conditions were expected in the morning, while otherwise partly cloudy and warm with isolated afternoon showers and thundershowers.

In Mpumalanga, it is expected to be cloudy along the escarpment with morning fog patches, otherwise partly cloudy and cool to warm with scattered showers and thundershowers from afternoon but isolated in the Lowveld where it will be hot.

The forecast for Limpopo was partly cloudy along the escarpment at first, otherwise fine and warm to hot becoming partly cloudy in the south and south-west with isolated showers and thundershowers from the afternoon.

A partly cloudy and warm to hot day has been predicted for the North West and Free State with afternoon thundershowers.

The Northern Cape is expected to be cloudy with cloudy with drizzle along the coast and the adjacent interior, otherwise partly cloudy and hot but cool in the west. Isolated showers and thundershowers were anticipated in the extreme east and south.

The wind along the coast will be fresh southerly to south-westerly becoming light to moderate by the evening, the weather service said.

In the Western Cape, partly cloudy and cool to warm conditions with isolated to scattered showers and thundershowers from late morning over the north-eastern parts, spreading across the province from the afternoon have been predicted. Widespread showers and thundershowers can be expected over the southern parts where flooding can be expected, while he wind along the coast will be strong south-easterly winds, but fresh in the south at first.

The western half of the Eastern Cape is anticipated to be cloudy and cool with showers south of the escarpment. Thunderstorms are expected in the north in the afternoon, spreading southwards, the weather service said, and isolated severe storms are possible over the escarpment north of Cradock.

The wind along the coast will be moderate to fresh easterly.

Cloudy and cool conditions with showers south of the escarpment is expected in the eastern half of the Eastern Cape. Thunderstorms are expected in the north in the afternoon, spreading southwards. 

Isolated severe storms are possible over the escarpment east of Aliwal North and the wind along the coast will be fresh to strong easterly, the SAWS said.

In KwaZulu-Natal, morning fog is expected over the interior while cloudy and warm but cool in places over the interior with widespread showers and thundershowers in the south-east, otherwise scattered but isolated in the north-east.

The wind along the coast will be moderate southerly to south-easterly but easterly to north-easterly along the north coast.