The South African Weather Service (SAWS) has warned that rain is expected to return to many provinces ahead of and during the coming Easter Weekend.
“The public is therefore urged to continue to monitor forecasts and warnings issued by SAWS,” it said in a statement on Tuesday.
The warning came in the wake of a trail of destruction in KwaZulu-Natal following heavy torrential rains on Monday evening. The inclement weather has resulted in damage to property and has claimed over 50 lives.
The SAWS said it would continue to monitor any further developments relating to this weather system and will issue subsequent updates as required.
Following widespread rainfall over much of the country over the weekend, the Weather Service said the cut-off low system responsible for the inclement weather began moving eastwards over KwaZulu-Natal and the Eastern Cape overnight.
The SAWS said while impact-based warnings were issued timeously, exceptional heavy rainfall on Monday evening and Tuesday exceeded expectations.
“At 4pm (on Monday), a Level 5 warning was issued for the coast and adjacent interior of KwaZulu-Natal. This was subsequently escalated to a Level 8 warning at 8pm last night.”
However, following reports of further impacts and persistent, heavy rainfall, SAWS upgraded the heavy rain warning to an Orange Level 9 on Tuesday.
Monday night rainfall reports in KwaZulu-Natal underscored the particularly heavy and extreme nature of the rainfall, with some 24-hour falls exceeding 200 mm. More noteworthy, said the SAWS, was that a few stations even reported 300 mm or more.
“A selection of the highest overnight rainfall measured in KwaZulu-Natal includes King Shaka International Airport (225 mm), Margate (311 mm), Mount Edgecombe (307 mm), Port Edward (188 mm) as well as Virginia airport (Durban north) with 304 mm.
“Such rainfall is of the order of values normally associated with tropical cyclones; however, SAWS must strongly emphasise that this system is not tropical in nature, nor is it a tropical cyclone. What was the reason for the heavy rain? In short, as alluded to earlier, a cut-off low in the upper reaches of the troposphere is currently moving seawards, off the eastern coast of South Africa.
“Cut-off lows are associated with widespread instability in the atmosphere, which can promote periods of prolonged rainfall, as witnessed over many of the interior provinces of South Africa at the weekend. For KwaZulu-Natal however, the effect of the cut-off low system has been markedly enhanced by the presence of sustained low-level maritime air which has been fed in from the southern Indian ocean, thus driving the system to produce more rainfall.”
The weather service said by Wednesday, the rainfall system would have weakened considerably, heralding a spell of a few days of settled dry weather.
“Furthermore, the public is urged and encouraged to regularly follow weather forecasts on television and radio,” it said.
Updated information in this regard will regularly be available at www.weathersa.co.za as well as via the SA Weather Service Twitter account @SAWeatherService – SAnews.gov.za
