Warm, dry winter still on the cards for SA, rains of La Niña beckon

‘The... multi-model rainfall forecast indicates mostly below-normal rainfall over most of the country during May-Jun-Jul (MJJ), Jun-Jul-Aug and Jul-Aug-Sep, except for some parts over KwaZulu-Natal, Eastern Cape and Mpumalanga for MJJ where above-normal rainfall is expected,” says the latest Climate Watch, which looks five months ahead. 

“Minimum and maximum temperatures are expected to be mostly above-normal countrywide for the forecast period,” it adds.

Winter is the dry season on the Highveld and much of the interior of the country, but it looks to be both drier and warmer than usual as the legacy of the drought unleashed by El Niño lingers.

“The anticipated below-normal rainfall coupled with above-normal temperatures are likely to increase water losses and reduce water storage levels through evapotranspiration and drought, among other factors, particularly in parts of the North West, Free State and Limpopo where a number of settlements are experiencing ongoing drought,” the Climate Watch says.

The SA Weather Service’s observations still see a fading El Niño in play, while other international forecasters such as the Australian Bureau of Meteorology say it is now over and that what is known as the El Niño-Southern Oscillation is currently in neutral territory.

This is a bit academic for South Africans as El Niño retracts its claws in this region at this time of the year anyway.

“El Niño does not have an effect on our weather this time of the year, so whether or not it is dying or still going is irrelevant,” Willem Landman, a professor of meteorology at the University of Pretoria, told Daily Maverick. 

More importantly, Landman’s forecast sees La Niña emerging towards springtime in these parts.

This is in line with most international forecasts, some of which see La Niña lifting off by July. 

El Niño, triggered by a warming of surface temperatures in the eastern Pacific, generally brings drought to southern Africa. The last one devastated the region’s staple maize harvest this year, among other impacts. 

Read more in Daily Maverick: South Africa’s neighbours bear the brunt of dry weather pattern

But some sectors, such as citrus, have escaped relatively unscathed, thanks in part to good moisture levels last spring which were a legacy of the previous prolonged La Niña event.

Read more in Daily Maverick: South African citrus farmers have reason to be upbeat after weathering El Niño 

La Niña arises when surface temperatures in the eastern Pacific cool, and its return will be welcome – provided the possible downpours don’t get too intense. 

Too much rain makes no grain and both weather patterns are becoming more extreme because of human-caused climate change.

The potential for too much rain is a concern in the early winter season in parts of KwaZulu-Natal, the Eastern Cape and Mpumalanga, which are expected to be unseasonably wet.

“There is an increased risk of waterlogging in areas receiving excessive rainfall, which can cause crop damage,” the Climate Watch warns.

Meanwhile, below-normal rainfall during the wet winter season in the southwestern parts of South Africa also poses challenges for agriculture as well as wider water supplies. 

On a brighter note, the milder winter should help Eskom to keep the lights on during the season of peak household demand and means South Africans won’t have to bundle up so much. 

The weather is often a double-edged sword, but at least El Niño has now been blunted. DM