The large El Niño expected in the Pacific Ocean could lead to hotter and drier conditions in many parts of South Africa this summer, raising concerns about heatwaves, drought, and water shortages.
South Africa is preparing for a warmer and drier season as the South African Weather Service (SAWS) warns that the powerful El Niño phenomenon developing in the Pacific Ocean could be the strongest on record, increasing the risk of drought, severe heatwaves, and water scarcity in the region.
SAWS reported that El Niño 2026/27 has already reached a very strong event level and is expected to intensify in the spring.
Ocean Temperature Rise
According to SAWS data, ocean temperatures in the east-central tropical Pacific are already exceeding the threshold used to classify El Niño as very strong. SAWS explained that a strong El Niño is a phenomenon where three-month average sea surface temperature anomalies over the east-central tropical Pacific exceed 1.5°C relative to climate, while for a very strong El Niño, this part of the ocean is 2°C warmer than normal.
The service warned that the latest forecasts indicate a possibility of exceeding this threshold by 3°C. SAWS notes that most El Niño events are associated with reduced rainfall and increased temperatures in South Africa, although the weather pattern does not guarantee drought with every such event.
Water Availability Concerns
SAWS's latest seasonal forecast for October to December 2026 predicts below-average rainfall across most of South Africa, accompanied by above-average temperatures. This same scenario is expected in January 2027, when most countries forecast drier and warmer conditions.
SAWS stated that the expected temperatures could significantly exceed historical thresholds for the October to December period. While this forecast raises concerns regarding water supply and agricultural conditions, SAWS emphasized that El Niño events can have varied regional outcomes. It was noted that the very strong El Niño of 1997/98 was associated with slightly above-average rainfall in some areas of South Africa's summer rainy season, so it should be considered that although the statistically most likely outcome in South Africa this summer is reduced rainfall, not every El Niño event leads to drought.
Potential for Severe Heatwaves
SAWS warned that the potential impact of the current El Niño could be amplified by ongoing global warming. The weather service noted that 2027 could be the hottest year on record if the expected very strong El Niño develops as forecasted. The 2015/16 El Niño was also mentioned, which was linked to unprecedented heatwaves in South Africa, and the warning that the region has continued to warm since then.
SAWS stated that if the 2026/27 El Niño event brings the expected reduction in rainfall to South Africa, it is highly likely that it will coincide frequently with severe heatwaves. The combination of reduced rainfall and extreme heat can increase pressure on already vulnerable water resources and weather-sensitive sectors.
Despite the alarming forecast, the weather service cautioned that uncertainty remains regarding the ultimate strength of El Niño and how its consequences will be distributed regionally. SAWS stated that it will continue to monitor the situation and inform disaster management agencies, weather-sensitive industries, the media, and the public. The public is strongly advised to track both seasonal and daily forecasts to prepare for possible heatwaves and other high-impact weather events.