South Africans are being urged to prepare for severe winter weather, with snow, flood risks and dangerous coastal conditions expected this week.

The South African Weather Service (SAWS) has warned of bitterly cold, wet and windy conditions across parts of South Africa during the first week of June.

While Monday and Tuesday are expected to be partly cloudy and cold, conditions are set to deteriorate from Wednesday, with snowfall forecast in parts of the Western and Northern Cape.

SAWS said very cold weather and rainfall are expected over the central and eastern interior of the Western Cape, as well as the southern parts of the Namakwa District in the Northern Cape.

"Light snowfall is expected over the mountain tops of the central and eastern parts of the Western Cape, and the higher-lying areas of the southern Namakwa District during this period," the weather service said.