Super El Niño – how it could affect South Africa’s maize prices

In southern Africa, the El Niño – caused by warmer sea surface temperatures in the Pacific Ocean which affect air pressure and wind directions – usually brings below-average summer rainfall and increases the risk of drought.

This means poor harvests of maize, a staple crop for many countries on the continent.

The current “super” El Niño is expected to reach very strong intensity , peaking towards the end of 2026 and lasting through at least February 2027.

Read more: Nigeria faces the world’s highest projected death toll from super El Niño heat: what could save lives The result is that many southern African countries may have to import more maize and prices will rise.

Maize prices in South Africa are influenced by the price of maize overseas, and not just by the local harvest.

This is because maize is bought and sold all over the world and so the maize futures prices (the contracts to buy or sell maize at an agreed price to be delivered later) on the Johannesburg Stock Exchange tend to follow prices on the Chicago Mercantile Exchange .

When those maize prices rise or fall, South African prices can follow, although the rand’s exchange rate and local supply and demand also affect them.

We are agricultural economists who recently set out to investigate whether South African maize prices still follow US maize prices during El Niño and La Niña periods, or whether these weather patterns make local prices more unstable.

La Niña events happen when Pacific Ocean sea temperatures are below the average, bringing generally favourable conditions for farming in southern Africa.

We analysed daily US and South African maize futures prices from 1997 to 2024, alongside exchange rates and records of El Niño and La Niña.

Using statistical models, we examined how price swings in the US market carried through to South Africa and whether these weather events made prices more unstable.

Our research found that US and South African maize prices generally moved together over the long run.

However, maize price volatility was more persistent during both El Niño and La Niña events.

During El Niño droughts, South Africa produces less maize, leaving buyers competing for a smaller supply.