Durban – KwaZulu-Natal residents are bracing for more severe thunderstorms on Thursday. The South African Weather Service (SAWS) has issued a Yellow Level 2 warning of severe thunderstorms with possible heavy downpours, strong damaging winds, hail and excessive lightning are expected over the western parts of KZN and Midlands on Thursday.
The Cape Town Weather Office has issued a Yellow Level 4 warning of severe thunderstorms, flooding and hail over parts of the Northern Cape and Western Cape while an Orange Level 6 warning of similar conditions is expected over the western and Central parts of the Western Cape.
SAWS said this is due to another cut-off low.
SAWS said this development follows close on the heels of a weather pattern, which dominated the western parts of the country over the past weekend.
“Usually a strong south-easter over the Western Cape during the summer months, is associated with fine, windy and warmer weather conditions. However, in the case of an upper-air cut-off low being present, it can lead to cloudy conditions and sometimes heavy rain, known as a ‘black south-easter’. This weather brings significant record-breaking rainfall and weather-related impacts,” SAWS said.
The forecaster said the cut-off low, (a deep, closed low pressure in the mid-troposphere that is displaced equatorward of the main westerly flow) had developed west of South Africa on Wednesday.
“Consequently, showers and thundershowers are expected to develop over the Namakwa interior from Thursday afternoon, spreading to the western and extreme northern parts of the Western Cape on Friday morning, when the system is expected to intensify. The more noteworthy and significant weather associated with the new upper-air system can be expected on Friday and Saturday mainly over the southern parts of Namakwa and the majority of the Western Cape.
“Widespread showers and thundershowers are likely to occur, with a chance that some of the storms may become severe, as was the case with the most recent system,” SAWS said.
The cut-off low is expected to weaken and move eastwards by Saturday, scattered to widespread showers and thundershowers will be likely over most of the Western Cape. The sustained nature of the showers and thundershowers will be due to the support of a ridging high pressure system over the Cape south coast, feeding in additional moisture from the ocean.
Residents are urged to brace for downpours averaging between 20mm and 30mm per hour with strong, gusty winds up to 90km/h in some parts as well as hail.
This will massively impact on driving and overflowing rivers and streams.
IOL