The South African Weather Service says it has been closely monitoring the development of two distinct weather systems during the past few days.

"The combined effect of a well-defined, intense cut-off low pressure system (located in the mid to upper regions of the atmosphere) together with the movement of a cold frontal system across South Africa, are expected to cause extreme weather conditions over most parts of the country from Friday 13th July 2012 onwards, persisting during this weekend.

The areas which will be the hardest hit are the Eastern Cape, parts of the Western Cape, the southern parts of the Northern Cape as well as the southern Free State.

WARNINGS:

Bitterly cold, wet and windy conditions are expected over the high ground of the Western and Eastern Cape, the interior of the Northern Cape as well as the Free State from Friday until Sunday. These conditions are also expected over parts of the North-West province, southern Gauteng and the south-western high ground of KwaZulu-Natal on Sunday. Maximum temperatures in these places are not expected to exceed 10 degrees Celsius.

Snowfalls, heavy in places, are expected over the central and eastern high ground of the Western Cape, the high ground of the Eastern Cape, Lesotho and the southern Drakensberg mountains, persisting until Sunday morning. This can lead to the closure of several mountain passes over these areas. Motorists are advised to seek information on the state of the mountain passes in these areas before venturing there. Light snowfalls are even possible over some places, where snowfall is seldom recorded, such as the western interior of the Northern Cape.

Heavy falls of rain are expected in the Overberg and Eden districts of the Western Cape as well as in places in the Eastern Cape on Friday and Saturday. This poses a serious risk of flash flooding in these places. Gale force southerly to south-easterly winds, accompanied by very rough seas, are expected between Lamberts Bay and Walvis Bay on Friday, persisting only along the Namibian coast on Saturday.

Read more at the South African Weather Service blog