Three cold fronts could cause very cold conditions, rain and snow up to 10cm deep in places this week until Thursday.
By Alani Janeke, senior journalist at African Farming and Landbouweekblad
Over the past weekend very cold conditions prevailed over the central and southern interior, as well as over the Highveld, and minimum temperatures of as low as -10°C occurred in the area of Smithfield in the southern Free State. More cold fronts will follow these cold conditions this week.
A series of frontal systems will move in over the country on Monday and Tuesday, resulting in very cold conditions with snow.
“Snow can occur quite widely across Southern Africa from 4 to 7 August. The possibility of heavy snow is highest in the northern interior of the Eastern Cape and Lesotho, and snow of up to 10cm deep or more may occur,” says Johan van den Berg, independent agricultural meteorologist.
Lighter snow is possible over the southern mountainous parts of the Northern Cape and the mountainous parts of the Western Cape, the Eastern Free State near the Drakensberg, as well as even in places in the North West.
“Because rain can also occur, heavier snow may fall than predicted if temperatures drop low enough.
“The frontal systems can move as far as Walvis Bay up the West Coast. Snow is also possible on 5 August over the high-lying parts of southern Namibia and light rain is possible from the Mariental area and further south and southeast.”
Further frontal systems and very cold conditions are forecast for 11 to 13 August.
Rainfall forecast shows winter is set to set in
Between 4 and 16 August, 30mm of rain or more could fall over parts of the Winelands, the Cape Town metropolis and the West Coast at, among others, Paarl, Stellenbosch, Malmesbury, Piketberg and Somerset West. Less than 15mm is forecast for the Overberg at, among others, Caledon, Bredasdorp and Swellendam, as well as on the Western Cape’s south coast such as at Mossel Bay and at Riversdale.
“Fronts are still trending more towards the west coast and the adjacent interior than the indications were a few weeks ago when they were trending more towards the south coast and the Eastern Cape coastal areas. This could be an indication that winter is far from over.”
Heavily cloudy conditions are forecast for most of August over the winter rainfall area. For Paarl, among others, the forecasts show that less than five full days of sunshine could occur by the end of August with approximately 15 days during which no direct sunshine will occur.
“This is very favourable for the accumulation of cold units because it limits the daytime temperatures, which often have a detrimental effect on the build-up of cold units when they are too high.”
Light rain of 10mm or less is forecast for most of the Northern Cape, the southern and eastern parts of the Free State and the entire Eastern Cape on 5 and 6 August. This rain will move further on 7 August, with somewhat heavier rainfall predicted for the eastern and northern parts of KwaZulu-Natal, Mpumalanga and even the eastern parts of Limpopo.
Temperature-wise, ‘winter is still far from over’
So far this winter the temperatures have been generally average to below average and this may remain so as winter is expected to be “far from over”. Colder temperatures are forecast for August than previously expected, although warmer periods may occur.
“Although warmer periods may occur, this does not mean the cold fronts will suddenly stop moving in over the country. The current cold period is a sign of this. Periods of warmer and colder temperatures will occur and this may continue until as late as October. Sporadic low minimum temperatures with frost may therefore still occur over the central to southern interior until very late after winter,” according to Van den Berg.
