The South African Weather Service (SAWS) is monitoring a potential risk of road flooding for motorists across the road network in Gauteng and other provinces this Saturday and Sunday (4 and 5 December 2021).
The weather service said that on a broader scale, residents
in Gauteng, Mpumalanga, the Free State and North West as well as the northern
areas of KwaZulu-Natal, the Eastern and Western Cape should be aware of the
risk of flash-flooding, especially in low-lying areas.
In a statement on Friday, they said they had alerted the public regarding expected incidents of localised flooding in Gauteng and KwaZulu-Natal.
"Impact-based warnings were similarly issued for North West, regarding severe thunderstorms accompanied by large amounts of small hail as well as strong, damaging winds.
"Apart from the extreme eastern areas of Vhembe and Mopani district municipalities in Limpopo on Saturday, showery conditions are expected across many areas in South Africa this weekend. However, flash-flooding can be expected in the low-lying areas over the eastern Free State, the southern half of North West and Gauteng. The midlands and northern areas of KwaZulu-Natal as well as Mpumalanga are also at risk of localised flooding. The residents of informal settlements, especially those located along river basins, are advised to take care, as such dwellings could be exposed to flooding. Disaster Management practitioners are also advised that some communities in the above-mentioned areas could become displaced and require emergency shelter."
SAWS said the extreme weather conditions anticipated in the days ahead relate to the expected development of a so-called “cut-off low pressure system” in the upper atmosphere, which is likely to be positioned over the western areas of the Northern Cape on Saturday.
"Severe thunderstorms associated with heavy downpours can be expected over the central and northern parts of the Eastern and Western Cape, the eastern areas of the Northern Cape as well as the western parts of the Free State and North West provinces.
"Motorists are further advised that driving conditions in some areas are likely to become dangerous due to poor visibility and slippery roads. Moreover, extra care should be taken when negotiating bridges and low-water crossings known to be susceptible to flash-flooding.
"Other thunderstorm-related hazards include the risk of large amounts of small hail which may cause damage to vehicles and infrastructure. Added to which, strong winds may result in difficulty in navigation at sea with short-term disruptions of small harbours and ports between Cape Columbine and Cape Agulhas on Saturday."
SAWS said as the weather system migrates further eastwards on Sunday, weather conditions are expected to shift to the east. However, on Sunday evening and overnight into Monday morning, the cut-off low will weaken into a steep upper trough feature. This means surface winds over the south-eastern parts of the country (including the Eastern Cape, KwaZulu-Natal and southern Free State) will be fairly strong during this particular period.
"A return to the familiar cycle of afternoon and early evening thunderstorms can be expected for the eastern parts of the country, extending from Monday to at least Thursday next week."
Keep an eye on updates to mainstream media (TV, radio and newspaper), the SAWS website (www.weathersa.co.za) and social media (twitter: @SAWeatherServic and Facebook: South African @WeatherServic)